[User] Please transcribe this text

[Assistant] Uhm, I'm using the word invention to refer to the thing that someone thought up a long time ago. And I'm using the verb invented. So someone obviously invented sliced bread.


[User] Please transcribe this text

[Assistant] My understanding is a long time ago bread was just a loaf and you would just take a chunk off. But at a certain point someone decided to slice it.


[User] Please transcribe this text

[Assistant] Our phrase. The phrase that I'm using today is the greatest thing since sliced bread.


[User] Please transcribe this text

[Assistant] So, we use this to refer to any newer invention that's just amazing.


[User] Please transcribe this text

[Assistant] It's an older phrase. It's not used a lot anymore, but I have heard it a couple of times in the last week. So let's say you're thinking about your smartphone. I don't have mine here. You could say, I love my smartphone. It's the greatest thing since sliced bread.


[User] Please transcribe this text

[Assistant] So for some reason, maybe just to be funny, we refer to sliced bread as the greatest invention of all times. I'm not sure it is. I think the internet might be the greatest invention of all time, but we use this to


[User] Please transcribe this text

[Assistant] So the telephone obviously is something that has changed a lot over time.


[User] Please transcribe this text

[Assistant] Uhm, I know in old movies when they use the telephone, they put something up to their ear and then they talk into another thing. Uhm, I think sometimes they even have a crank on them. But the modern telephone, I think, has been in all of our homes for our entire lives.


[User] Please transcribe this text

[Assistant] My grandparents, when they were young, uh, did not have telephones. So even though it seems like a relatively normal thing to have, it is somewhat of a recent invention in terms of human history.


[User] Please transcribe this text

[Assistant] Uh, the telephone allows you to phone people. Notice we've shortened the word. I don't often say, oh, I'm going to telephone my brother tonight. That just doesn't work.


[User] Please transcribe this text

[Assistant] I would say I'm going to phone my brother or I'm going to call my brother. So the telephone, cool invention.


[User] Please transcribe this text

[Assistant] I don't know if you guys want to start voting on what is the, um, best invention of all time, but certainly the telephone is really cool. And there are a lot of phrases that come from the word telephone. I picked the one phone tag, uh, because it's probably the most common one that I hear right now.


[User] Please transcribe this text

[Assistant] Phone tag is when you phone someone and they're not available so you leave a message. They listen to your message later in the day and then they phone you


[User] Please transcribe this text

[Assistant] But you're not available so they leave a message. And then you listen to their message and then you phone them and leave a message. And then they listen to you and we call that phone tag. Phone tag is then, uh, when you're trying to get a hold of someone.


[User] Please transcribe this text

[Assistant] But you constantly get their answering machine instead and you leave a voicemail or you leave a message. That's how we talk about that. So, uh, phone tag is interesting because I don't often phone people anymore. I'm not sure.


[User] Please transcribe this text

[Assistant] Nowadays I tend to send text messages and sometimes email. That's probably my primary method of communication. Brent in the chat says the best invention no doubt is the flushable toilet. I don't actually have that on my slides, Brent, but that certainly is an amazing invention.


[User] Please transcribe this text

[Assistant] Years ago, people didn't even have bathrooms in their homes. They had an outhouse. So you had to go outside to use the bathroom. I'm not sure what that would have been like in the winter. Probably not very fun. Uhm.


[User] Please transcribe this text

[Assistant] The next invention is the camera. So a long time ago we had cameras that took film and you needed to put film in the camera so that you could take a picture.


[User] Please transcribe this text

[Assistant] For those of you that are just joining us and you're wondering how is this an English lesson, it's important to listen to the phrases I choose to use when I'm talking about each item because there's actually a lot to learn


[User] Please transcribe this text

[Assistant] In the descriptions I'm giving. So for instance, with cameras, you use a camera to take a picture. When we used to put film in the camera, we would then need to get the film developed. And once the film was developed, you could see, uh, whether the pictures turned out. These days, everything is a lot faster.


[User] Please transcribe this text

[Assistant] Good, is it in focus? Uhm, do you like the lighting in the photo and all of those kinds of things? So, the camera, an amazing invention. Uhm, cameras also take different lenses. Uhm, you might have a camera where you cannot remove the lens, but some cameras have interchangeable lenses.


[User] Please transcribe this text

[Assistant] Also used to take photos. We often use the word picture and photo interchangeably. So a lot of times I'll say, hey, I took a really good picture or took a really cool picture of Oscar today. I'll send it to you.


[User] Please transcribe this text

[Assistant] We don't often say, I took a really cool photo of Oscar, but we do use the word still quite a bit. Uhm, the phrase I chose from the


[User] Please transcribe this text

[Assistant] Uh, invention of the camera is the phrase a picture is worth a thousand words. So this phrase simply means exactly what you think it means. Sometimes when you are trying to explain something to someone, either in a conversation or in writing,


[User] Please transcribe this text

[Assistant] You have to use a lot of words to get your meaning across. You have to use a lot of words so that they can understand what you are talking about. But sometimes if you can just show them a picture, it's worth a thousand words. So you can see here, this is a picture of the Horseshoe Falls in Niagara Falls.


[User] Please transcribe this text

[Assistant] If I wanted to describe the horseshoe falls to you in writing, it would probably take many, many words. I would need to say it's shaped like a horseshoe. A horseshoe is the thing that people put on the feet of horses, and it's this shape. Notice I'm already trying to use images to communicate it, but if I show you a picture,


[User] Please transcribe this text

[Assistant] You immediately know what the horseshoe falls looks like. So, we have a phrase, a picture is worth a thousand words. Uhm, simply because yes, pictures are just a much easier way to explain what something looks like. Let's do a few more. The telescope.


[User] Please transcribe this text

[Assistant] So the telescope was invented so we could look at the heavens. Notice I used the word heaven?


[User] Please transcribe this text

[Assistant] So in religion, people sometimes talk about heaven and hell.


[User] Please transcribe this text

[Assistant] Uhm, but we also talk about the night sky sometimes as the heavens. So the telescope was a device that was invented so that we could look at things really really far away. Uhm, uh, you might also know what a binoc, what binoculars are. Binoculars are, uhm,


[User] Please transcribe this text

[Assistant] Similar to a telescope, but there are two uhm.


[User] Please transcribe this text

[Assistant] Not sure what they're called. There's two viewing things beside each other. Not a binocular expert. But the telescope was invented so we could get a closer look at the moon and the stars and all of the things that we see in the night sky.


[User] Please transcribe this text

[Assistant] So you'll notice with telescope, I did not have a phrase to teach you, but here's a microscope and I do have a phrase for this one. Uh, the microscope was invented kind of...


[User] Please transcribe this text

[Assistant] It's similar to the telescope but instead of looking at things far away, the microscope is used for looking at things that are really, really small.


[User] Please transcribe this text

[Assistant] If you went to high school and had a science class, you most likely had microscopes and you most likely used microscopes to look at maybe the cells of your skin. You might have used the microscope to maybe you


[User] Please transcribe this text

[Assistant] Uh, poked your finger and put a little bit of blood on the slide.


[User] Please transcribe this text

[Assistant] We have an English phrase to put something under the microscope. So let's say the police think.


[User] Please transcribe this text

[Assistant] They might put your life under the microscope for a bit.


[User] Please transcribe this text

[Assistant] All this phrase means is that someone is paying very close attention to something. So when you put something under the microscope or you put someone under the microscope, it means you're watching them very closely to see what they do. Maybe, uh, you didn't.


[User] Please transcribe this text

[Assistant] Maybe you cheated on your taxes. So in Canada, you have to file your taxes every year. You have to tell the government.


[User] Please transcribe this text

[Assistant] The next invention is the light bulb. Of course, if we did not have light bulbs, I would look more like this.


[User] Please transcribe this text

[Assistant] There we go. Oh, my camera's adjusting now. Uh, whoa, that was quite bright. But if we did not have light bulbs, we would not be able to do things at night.


[User] Please transcribe this text

[Assistant] Many, many years ago, people simply had fires in their fireplace and maybe they had some lanterns in their house. Maybe they used candles to light their homes. Uhm, but eventually the light bulb was invented and because of electricity, people were able to do more things at night.


[User] Please transcribe this text

[Assistant] I think the light bulb is incredibly important especially in Canada where it gets dark really early.


[User] Please transcribe this text

[Assistant] So you'll notice in some of my videos, if I'm out late at night in the summer, it's still quite sunny. But if you go outside at night in January, uhm, like by 4.30, 5 o'clock in the afternoon, it's already starting to get dark. So the light bulb has really changed the world.


[User] Please transcribe this text

[Assistant] And of course, just a quick little note, there are incandescent light bulbs. That's the older style. There are fluorescent light bulbs. Those are the kinds that are long tubes. And now most of our lighting, most of our light bulbs are LED light bulbs. So we kind of.


[User] Please transcribe this text

[Assistant] Have innovated, uhm, quite a bit along the way with light bulbs.


[User] Please transcribe this text

[Assistant] So here's the phrase for light bulb, uh, when you say a light bulb went on in my head or a light bulb went off in my head. There's two versions of it. They mean the same thing.


[User] Please transcribe this text

[Assistant] It means you had an idea or you suddenly solved a problem you were thinking about. Okay. So let's say I needed to go to the grocery store and the post office and to the restaurant after work.


[User] Please transcribe this text

[Assistant] But I wasn't sure how I was going to do that all at once and then maybe a light bulb goes on in my head or a light bulb goes off in my head and I think I can drop my son off at the restaurant. He can order food.


[User] Please transcribe this text

[Assistant] Then I can go and buy the things I need to and pick them up later. So when you say a light bulb went off in my head, or when you say a light bulb went on in my head, it simply means you had a good idea or you thought of a solution to a problem. So that's how that would work.


[User] Please transcribe this text

[Assistant] Uh, the printing press. Uhm, there's probably gonna be some inventions I don't mention, but I think this one is incredibly important, okay? Before the invention of the printing press, everything needed to be written by hand with a pen or maybe a


[User] Please transcribe this text

[Assistant] This is an old phrase. We don't use it as much anymore. But when you say something is hot off the press, it means the news you are sharing is very, very


[User] Please transcribe this text

[Assistant] Okay, so if you say, um, hey, I just read this, it's hot off the press. It simply means that it's news that just happened. Okay. So if the president of the United States announced that he was not running for reelection, if that was news that just happened, you would say it was hot off the press.


[User] Please transcribe this text

[Assistant] Vaccines. So, if we were gonna talk about some of the most important inventions, I would say vaccines are incredibly important.


[User] Please transcribe this text

[Assistant] Vaccines are something that help you build immunity to a disease so that you don't get the disease. If there was a vaccine right now for coronavirus, I would want to get it, okay? I know they are testing vaccines right now in the world. You're probably hearing that on the news quite often.


[User] Please transcribe this text

[Assistant] Many different countries have gotten close to having working vaccines.


[User] Please transcribe this text

[Assistant] In the winter, you either get the flu or you get a cold. Those are the two most common illnesses in the winter here.


[User] Please transcribe this text

[Assistant] And no specific phrases for this one, but I do want to share this when you get.


[User] Please transcribe this text

[Assistant] A shot, okay. So you saw earlier, here's a needle.


[User] Please transcribe this text

[Assistant] When they put it in your arm or in the cheek of your butt, wherever you're getting the shot, uhm, we call it a shot. Okay. Sounds kind of funny, but the nurse gives you a shot. That's how, that's how we say it. And these are the two phrases that they most often say. They say, this won't hurt a bit.


[User] Please transcribe this text

[Assistant] Which isn't true, it actually does hurt a little bit. But they'll say, okay, roll up your sleeve, uhm, this won't hurt a bit. And then they usually wipe your, uhm, your shoulder with a little bit of, uh, an alcohol swab to disinfect it. And then,


[User] Please transcribe this text

[Assistant] Uhm, I think the second phrase is actually more truthful than the first one. When you say this won't hurt a bit, I don't quite, I don't feel like that's totally truthful.


[User] Please transcribe this text

[Assistant] Uhm, let me get to the next one here. The automobile. So when you talk about great inventions and someone asked earlier what I think the most important invention was, I think it's hard to say because so many inventions are so important. The automobile obviously is another invention that changed the world.


[User] Please transcribe this text

[Assistant] It changed the world in the sense that you could now drive and visit people who were far away. Instead of taking a horse and bucky, you could just jump in your car and you could drive there. The automobile allowed people to work, to live further away from where they worked.


[User] Please transcribe this text

[Assistant] So it allowed cities to have areas like suburbs and subdivisions where people live outside the city and then they drive into the city to go to work. When you drive from outside the city into the city, it's called a commute. You are called a commuter and you would say, yeah, I commute to work every day.


[User] Please transcribe this text

[Assistant] So when you commute, you can also take the subway or the train, but generally, uh, in North America, many people drive to work every day. So the automobile, I would say, let's say it's in the top 10. It's one of the top 10 most important inventions.


[User] Please transcribe this text

[Assistant] And then let's say here, oh yeaah, this is the phrase I chose. To put the pedal to the metal. So uhm, you can see the speedometer in this car is at 190 kilometers per hour. Uhm, that is very very fast.


[User] Please transcribe this text

[Assistant] If it's at 190 miles per hour, that's incredibly fast. But in a car, you have a gas pedal.


[User] Please transcribe this text

[Assistant] The passenger and the person isn't driving fast enough. You could say, come on, I'm in a hurry. Put the pedal to the metal.


[User] Please transcribe this text

[Assistant] Which doesn't mean to put it all the way to the floor, but it does mean that you want them to speed up. The other phrase we say is to floor it. So if you're in a hurry and you're not driving, you could say, come on, floor it. I need to get to work on time. So.


[User] Please transcribe this text

[Assistant] Floor it means to push the gas pedal all the way to the floor. Uhm, the next invention is the clock. By the way, uh, before there was a clock, I think we just looked at the sun. I have no idea how people knew what time it was when it was a cloudy day. Like today the sun is behind the clouds. Uhm, but eventually someone invented the clock.


[User] Please transcribe this text

[Assistant] Uhm, interestingly enough, when the clock was invented, most people only had a clock tower in their town.


[User] Please transcribe this text

[Assistant] And if you lived way outside of the town, if you couldn't hear the bells from the clock tower, you wouldn't know what time it was. So very interesting. People had hourglasses, right? So you, it's sand and then the sand would fall through the hourglass.


[User] Please transcribe this text

[Assistant] Uh, but the clock, I think, is a pretty cool invention. Uh, Key Park says internet is the greatest invention in the world, I think, so that we can learn English with Bob from all over the world. It is certainly a cool, cool, uh, invention for sure.


[User] Please transcribe this text

[Assistant] Let's see here. Brent says he works with a teacher named Susan. She's not lazy at all. Thanks, Brent. Uhm, and then there were many phrases related to clocks and the one I chose was the phrase around the clock.


[User] Please transcribe this text

[Assistant] Because we have light at night and because we can function 24 hours a day, we now have the phrase around the clock. You can use this literally, like if you worked for 24 hours straight, you could say I worked around the clock.


[User] Please transcribe this text

[Assistant] But we usually use this kind of figuratively to exaggerate.


[User] Please transcribe this text

[Assistant] I'm really tired. I've been working around the clock. Okay. You can also say that a store is open around the clock. Okay. So that's why I picked the open 24 hours. Uhm, but when something is open around the clock, it simply means it's open all the time.


[User] Please transcribe this text

[Assistant] If you say that you work around the clock, it means that you're working quite a bit.


[User] Please transcribe this text

[Assistant] Uhm, the refrigerator. Sorry, my nose is just a little bit itchy right now. I don't want to scratch my nose. It's rude to pick your nose on screen. I don't, I don't pick my nose, okay? Only kids pick their nose.


[User] Please transcribe this text

[Assistant] Uh, refrigerator. So, a long time ago there was no way to keep food cold. Uh, maybe you put your food in a stream. I don't know. Eventually people would, uh,


[User] Please transcribe this text

[Assistant] In winter, countries that have winter, they would cut large blocks of ice in the summer, in the winter months and store them so they could use them in the summer as ice blocks. But eventually someone invented the refrigerator.


[User] Please transcribe this text

[Assistant] A great invention that we do not often think about the fact that we can go buy fresh food. We can bring it home and stick it in a refrigerator and.


[User] Please transcribe this text

[Assistant] The refrigerator is the central part of my home. It is the item in my, it is the thing in my home that gets opened the most, I think.


[User] Please transcribe this text

[Assistant] So we ended up, I thought, oh, there's a number of different phrases related to fridge, but I thought I would talk about fridge magnets because this is something.


[User] Please transcribe this text

[Assistant] That was inadvertently invented. A fridge magnet is something that is magnetic, so a magnet will stick to something that is metal.


[User] Please transcribe this text

[Assistant] So the door of the fridge, the fridge door in many homes is a place where people put things and they usually put it there with a fridge magnet. So a fridge magnet is a magnet usually from, like these are probably all from different companies.


[User] Please transcribe this text

[Assistant] But on our fridge, sometimes we'll put a note on the fridge door and we'll put a magnet, a fridge magnet on it to hold it there. So, fridge magnets are very, very cool. Uhm, something that didn't exist before fridges existed.


[User] Please transcribe this text

[Assistant] When you discover something, it means it already exists and you just figured out how to use it or what it is. But when you invent something, you actually create it. So I would say that a long time ago, electricity was discovered.


[User] Please transcribe this text

[Assistant] And that because of that people eventually created batteries. So batteries have a positive and negative side. So I'm not sure you can see the fly trying to learn English from me. Uhm, and batteries have also allowed us to have a modern world because it allows us to have electricity in remote places.


[User] Please transcribe this text

[Assistant] Uhm, I chose the phrase to recharge your batteries. So sometimes we pretend that humans have batteries at the end of a long day. Sometimes if I had a hammock, I should buy one, that's a hammock.


[User] Please transcribe this text

[Assistant] I'm not doing a live English lesson because I just need a day where I can recharge my batteries. I need a day where I don't talk.


[User] Please transcribe this text

[Assistant] Paper. So paper was invented a very, very long time ago and it allowed us to write things down.


[User] Please transcribe this text

[Assistant] Before we had paper, before we had different ways to record knowledge, people simply needed to tell, to communicate knowledge to the next generation orally. They literally needed to sit around and tell someone how to do something.


[User] Please transcribe this text

[Assistant] Paper and all of the things before paper that we could write on, uhm, I'm sure there were many things before actual paper allowed us to record our knowledge.


[User] Please transcribe this text

[Assistant] Uhm, and then I chose this phrase even though it's not directly related to paper. It kind of is. We have a phrase that the pen is mightier than the sword. So what this means is that when nations fight, when there is war, they do that to solve disagreements between them.


[User] Please transcribe this text

[Assistant] But instead of war, sometimes or most times, if you can just communicate


[User] Please transcribe this text

[Assistant] You could probably solve your problem without having to fight with each other. So uhm,


[User] Please transcribe this text

[Assistant] When we say this as well, we mean that if you wanted...


[User] Please transcribe this text

[Assistant] If you wanted someone to think, oh, look at that. My finger just got stuck in my microphone. One sec here. I was not expecting that to happen.


[User] Please transcribe this text

[Assistant] If you're wondering what I'm doing, I'm not waving at you. I'm trying to get the fly to stop bugging me.


[User] Please transcribe this text

[Assistant] If I write a letter to the fly and ask him to stop bugging me, it's not going to work in this situation. This phrase is not true, but often.


[User] Please transcribe this text

[Assistant] Before the automobile, there were several ways to get around in the world. I think the bicycle is one of the coolest inventions because it does not pollute. You just simply use your own power to pedal the bike and you use the bike to go various places. I'm amazed at how


[User] Please transcribe this text

[Assistant] Some people use cycle, but we often just say bike. My kids like to bike around in the driveway. Uh, all of my kids have bikes and they love to bike. So I've just used bike in a number of different ways there.


[User] Please transcribe this text

[Assistant] Let me see where I am here. Okay. Uhm, and then we have a phrase in English. We say it's like riding a bike. We use this phrase when we're talking about something.


[User] Please transcribe this text

[Assistant] That once you learn how to do it, you don't forget how to do it. So there are some things where when you learn how to do it, you can quickly forget how to do it. But there are other things that once you learn how to do it, we say it's like riding a bike.


[User] Please transcribe this text

[Assistant] Because once you learn to ride a bike, you don't usually forget how to ride a bike. So there are simple things in life, like if I show one of my kids how to fry an egg.


[User] Please transcribe this text

[Assistant] They're not going to forget how to fry an egg. So I could say, Hey, it's really easy. I'll show you how to fry an egg. Um, after I show you, you'll, you'll have no problem doing it yourself. It's like riding a bike. Okay. So the phrase it's like riding a bike simply means that it's something that you find easy to remember and easy to do later again.


[User] Please transcribe this text

[Assistant] Television. So television has kind of changed in the last little while. It's not what it used to be. When I was a kid, we would sit down at night and watch television. We would have, I think we had 10 channels, maybe 11, and we would look in the TV guide to see what was going to be on. And then we would watch television nowadays.


[User] Please transcribe this text

[Assistant] People still watch television, but they also watch Netflix and they watch YouTube. So,


[User] Please transcribe this text

[Assistant] Watching things like videos has changed quite a bit. So television is a cool invention. Before television there was radio, uhm, and people would just listen, but eventually they figured out how to send


[User] Please transcribe this text

[Assistant] And this created something called the TV dinner. So the TV dinner, uhm, we still use this word even though people don't always eat these in front of the TV. Uhm, but if you go to the frozen food section of a grocery store,


[User] Please transcribe this text

[Assistant] Uhm, there is a number of TV dinners. A TV dinner is a frozen meal.


[User] Please transcribe this text

[Assistant] That you can quickly heat up in a microwave and then eat. They're not very tasty. They're not very healthy. We do not buy TV dinners.


[User] Please transcribe this text

[Assistant] We probably would call them frozen dinners now. I think TV dinner is an older phrase. Uh, maybe Brent can let us know in the chat whether people still call these TV dinners, um, down in the United States. Let me just check something here. Someone has mentioned.


[User] Please transcribe this text

[Assistant] There we go. Uhm, yeaah, I'm not sure. We would call them frozen dinners, but they are definitely TV dinners. They're meant to heat up quick and then, uh, and then eat in front of the TV.


[User] Please transcribe this text

[Assistant] And then here we go. This is actually the last slide of the lesson. It's for, uh, airplane. So we earlier had someone mentioned, uh, who do you think actually invented the airplane? That's a tricky one because different people in different parts of the world were working on.


[User] Please transcribe this text

[Assistant] I think some of the most successful early flights were by the Wright brothers, but I don't wanna say they invented it. I definitely know they made some huge leaps forward.


[User] Please transcribe this text

[Assistant] Uh, in flying a machine through the sky. I think they actually called them flying machines before they called them airplanes.


[User] Please transcribe this text

[Assistant] The airplane has also changed the world. Okay. The airplane has.


[User] Please transcribe this text

[Assistant] Allowed people to visit other countries a lot more easily, to go on vacations in places where they never would have been able to before. Before the airplane, everyone needed to just go on a boat or a ship.


[User] Please transcribe this text

[Assistant] If I wanted to visit Europe 150 years ago, I would have needed to take a ship or a boat. Uh, now I can just jump on an airplane and I'm there in six hours. So the airplane and then the phrase I chose for airplane is the phrase red eye.


[User] Please transcribe this text

[Assistant] Uh, red eye is how we refer to a flight that is at night, okay? So I actually heard this word just the other day at my work. Someone had gone out west to visit family and they came back on a red eye.


[User] Please transcribe this text

[Assistant] So when you call it a red eye, it's simply a flight that leaves in the evening and usually lands in the evening. So instead of flying during the day, you fly at night.


[User] Please transcribe this text

[Assistant] I eat too much, and I feel bad now.


[User] Please transcribe this text

[Assistant] I eat too much, and I feel bad now.


[User] Please transcribe this text

[Assistant] I eat too much, and I feel bad now.


[User] Please transcribe this text

[Assistant] She said she couldn't come because she had to work overtime.


[User] Please transcribe this text

[Assistant] She said she couldn't come because she had to work overtime.


[User] Please transcribe this text

[Assistant] She said she couldn't come because she had to work overtime.


[User] Please transcribe this text

[Assistant] I'll run some errands inside. Please wait for me for a second here.


[User] Please transcribe this text

[Assistant] I'll run some errands inside. Please wait for me for a second here.


[User] Please transcribe this text

[Assistant] I'll run some errands inside. Please wait for me for a second here.


[User] Please transcribe this text

[Assistant] His number was noted in this paper. And you can contact him.


[User] Please transcribe this text

[Assistant] His number was noted in this paper. And you can contact him.


[User] Please transcribe this text

[Assistant] His number was noted in this paper. And you can contact him.


[User] Please transcribe this text

[Assistant] Which pair of sports shoes do you want to buy?


[User] Please transcribe this text

[Assistant] Which pair of sports shoes do you want to buy?


[User] Please transcribe this text

[Assistant] Which pair of sports shoes do you want to buy?


[User] Please transcribe this text

[Assistant] It's windy outside. Please close the window.


[User] Please transcribe this text

[Assistant] It's windy outside. Please close the window.


[User] Please transcribe this text

[Assistant] It's windy outside. Please close the window.


[User] Please transcribe this text

[Assistant] I can't understand this English passage. Please translate it for me.


[User] Please transcribe this text

[Assistant] I can't understand this English passage. Please translate it for me.


[User] Please transcribe this text

[Assistant] I can't understand this English passage. Please translate it for me.


[User] Please transcribe this text

[Assistant] If you aren't in a hurry, please sit down and have a talk with me.


[User] Please transcribe this text

[Assistant] If you aren't in a hurry, please sit down and have a talk with me.


[User] Please transcribe this text

[Assistant] If you aren't in a hurry, please sit down and have a talk with me.


[User] Please transcribe this text

[Assistant] Our tenth wedding anniversary is the day after tomorrow.


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[Assistant] Our tenth wedding anniversary is the day after tomorrow.


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[Assistant] Our tenth wedding anniversary is the day after tomorrow.


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[Assistant] Dad, I want to go swimming during this summer vacation.


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[Assistant] Dad, I want to go swimming during this summer vacation.


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[Assistant] Dad, I want to go swimming during this summer vacation.


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[Assistant] Why are we eating noodles again? It is the third day for that.


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[Assistant] Why are we eating noodles again? It is the third day for that.


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[Assistant] Why are we eating noodles again? It is the third day for that.


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[Assistant] I'll be late for work, so I won't have breakfast.


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[Assistant] I'll be late for work, so I won't have breakfast.


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[Assistant] I'll be late for work, so I won't have breakfast.


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[Assistant] I study in Canada and have a work.


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[Assistant] I study in Canada and have a work.


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[Assistant] I study in Canada. And have a work.


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[Assistant] Hello, Miss Wei? Do you have time tomorrow?


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[Assistant] Hello, Miss Wei? Do you have time tomorrow?


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[Assistant] Hello, Ms. Wei? Do you have time tomorrow?


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[Assistant] You are advised to have a good rest and take the medicine on time.


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[Assistant] You are advised to have a good rest and take the medicine on time.


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[Assistant] This coat is very nice, isn't it? Just needs over a hundred dollars.


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[Assistant] This coat is very nice, isn't it? Just needs over a hundred dollars.


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[Assistant] This coat is very nice, isn't it? Just needs over a hundred dollars.


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[Assistant] What are you doing? I've been waiting for you for half an hour.


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[Assistant] What are you doing? I've been waiting for you for half an hour.


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[Assistant] What are you doing? I've been waiting for you for half an hour.


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[Assistant] What kind of movie ticket do you like? The front one or back one?


[User] Please transcribe this text

[Assistant] What kind of movie ticket do you like? The front one or back one?


[User] Please transcribe this text

[Assistant] What kind of movie ticket do you like? The front one or back one?


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[Assistant] I have finished this book. You can take it back and take your time.


[User] Please transcribe this text

[Assistant] I have finished this book. You can take it back and take your time.


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[Assistant] I have finished this book. You can take it back and take your time.


[User] Please transcribe this text

[Assistant] How many days do you usually have for New Year's Day?


[User] Please transcribe this text

[Assistant] How many days do you usually have for New Year's Day?


[User] Please transcribe this text

[Assistant] How many days do you usually have for New Year's Day?


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[Assistant] It's so light. Add some salt, please.


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[Assistant] It's so light. Add some salt, please.


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[Assistant] It's so light. Add some salt, please.


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[Assistant] If you can't come tomorrow, I'll look for you.


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[Assistant] If you can't come tomorrow, I'll look for you.


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[Assistant] If you can't come tomorrow, I'll look for you.


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[Assistant] We work at nine o'clock. Why are you here at six?


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[Assistant] We work at nine o'clock. Why are you here at six?


[User] Please transcribe this text

[Assistant] We work at nine o'clock. Why are you here at six?


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[Assistant] Are you losing weight? Why not eat some?


[User] Please transcribe this text

[Assistant] Are you losing weight? Why not eat some?


[User] Please transcribe this text

[Assistant] Are you losing weight? Why not eat some?


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[Assistant] The vegetables and fruits in this shop are very fresh.


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[Assistant] The vegetables and fruits in this shop are very fresh.


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[Assistant] The vegetables and fruits in this shop are very fresh.


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[Assistant] We live near the sea, and it is windy here.


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[Assistant] We live near the sea, and it is windy here.


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[Assistant] I bought two movie tickets. Let's go to see it.


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[Assistant] I bought two movie tickets. Let's go to see it.


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[Assistant] I bought two movie tickets. Let's go to see it.


[User] Please transcribe this text

[Assistant] Which would you like? Coffee or black tea?


[User] Please transcribe this text

[Assistant] Which would you like? Coffee or black tea?


[User] Please transcribe this text

[Assistant] Which would you like? Coffee or black tea?


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[Assistant] I am so tired with three meetings in a row.


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[Assistant] I am so tired with three meetings in a row.


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[Assistant] I am so tired with three meetings in a row.


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[Assistant] That store is on sale today. Let's have a look.


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[Assistant] That store is on sale today. Let's have a look.


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[Assistant] That store is on sale today. Let's have a look.


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[Assistant] What a coincidence. I am just going to call you.


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[Assistant] What a coincidence. I am just going to call you.


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[Assistant] What a coincidence. I am just going to call you.


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[Assistant] It's almost 12 p.m. You'd better go to sleep.


[User] Please transcribe this text

[Assistant] It's almost 12 p.m. You'd better go to sleep.


[User] Please transcribe this text

[Assistant] It's almost 12 p.m. You'd better go to sleep.


[User] Please transcribe this text

[Assistant] The weather here is still like summer, although now is the end of December.


[User] Please transcribe this text

[Assistant] The weather here is still like summer, although now is the end of December.


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[Assistant] The weather here is still like summer, although now is the end of December.


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[Assistant] Is it the first time for you to travel in Spain?


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[Assistant] Is it the first time for you to travel in Spain?


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[Assistant] She usually arrives at company earlier than me.


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[Assistant] She usually arrives at company earlier than me.


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[Assistant] You have watched your phone for a long time. What are you looking at?


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[Assistant] You have watched your phone for a long time. What are you looking at?


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[Assistant] You have watched your phone for a long time. What are you looking at?


[User] Please transcribe this text

[Assistant] Where would you like to go for your trip next year?


[User] Please transcribe this text

[Assistant] She often hides behind her mother when there is a stranger.


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[Assistant] She often hides behind her mother when there is a stranger.


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[Assistant] She often hides behind her mother when there is a stranger.


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[Assistant] You love dogs so much. Why don't you get one?


[User] Please transcribe this text

[Assistant] You love dogs so much. Why don't you get one?


[User] Please transcribe this text

[Assistant] You love dogs so much. Why don't you get one?


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[Assistant] I want to have a vacation in Europe this fall.


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[Assistant] I want to have a vacation in Europe this fall.


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[Assistant] I want to have a vacation in Europe this fall.


[User] Please transcribe this text

[Assistant] These socks have worn out. Throw them away.


[User] Please transcribe this text

[Assistant] These socks have worn out. Throw them away.


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[Assistant] These socks have worn out. Throw them away.


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[Assistant] What did he say? You are unhappy.


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[Assistant] What did he say? You are unhappy.


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[Assistant] What did he say? You are unhappy.


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[Assistant] We decided to go to Paris, and we would like a local guide. Can you recommend one for us?


[User] Please transcribe this text

[Assistant] We decided to go to Paris, and we would like a local guide. Can you recommend one for us?


[User] Please transcribe this text

[Assistant] We decided to go to Paris, and we would like a local guide. Can you recommend one for us?


[User] Please transcribe this text

[Assistant] What is the common interest for your husband and you?


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[Assistant] What is the common interest for your husband and you?


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[Assistant] What is the common interest for your husband and you?


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[Assistant] I feel there is something wrong with my nose after I got here. And I have runny nose and sneezing.


[User] Please transcribe this text

[Assistant] I feel there is something wrong with my nose after I got here. And I have runny nose and sneezing.


[User] Please transcribe this text

[Assistant] I feel there is something wrong with my nose after I got here. And I have runny nose and sneezing.


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[Assistant] I don't know any of those people. Please introduce them.


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[Assistant] I don't know any of those people. Please introduce them.


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[Assistant] I don't know any of those people. Please introduce them.


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[Assistant] The child caught a cold and has a runny nose, a stuffy nose, and a cough.


[User] Please transcribe this text

[Assistant] The child caught a cold and has a runny nose, a stuffy nose, and a cough.


[User] Please transcribe this text

[Assistant] The child caught a cold and has a runny nose, a stuffy nose, and a cough.


[User] Please transcribe this text

[Assistant] The school will start tomorrow. Have you finished your summer homework?


[User] Please transcribe this text

[Assistant] The school will start tomorrow. Have you finished your summer homework?


[User] Please transcribe this text

[Assistant] The school will start tomorrow. Have you finished your summer homework?


[User] Please transcribe this text

[Assistant] I am a little thirsty, and I want to drink some water.


[User] Please transcribe this text

[Assistant] I am a little thirsty, and I want to drink some water.


[User] Please transcribe this text

[Assistant] I am a little thirsty, and I want to drink some water.


[User] Please transcribe this text

[Assistant] This black tea is so good. Where did you get it?


[User] Please transcribe this text

[Assistant] This black tea is so good. Where did you get it?


[User] Please transcribe this text

[Assistant] This black tea is so good. Where did you get it?


[User] Please transcribe this text

[Assistant] Do you have any cash? There is no cash in my pocket.


[User] Please transcribe this text

[Assistant] Do you have any cash? There is no cash in my pocket.


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[Assistant] Do you have any cash? There is no cash in my pocket.


[User] Please transcribe this text

[Assistant] Can you see Mount Fuji from the hotel you live?


[User] Please transcribe this text

[Assistant] Can you see Mount Fuji from the hotel you live?


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[Assistant] Can you see Mount Fuji from the hotel you live?


[User] Please transcribe this text

[Assistant] What day is it? Why do you cook so many delicious foods?


[User] Please transcribe this text

[Assistant] What day is it? Why do you cook so many delicious foods?


[User] Please transcribe this text

[Assistant] What day is it? Why do you cook so many delicious foods?


[User] Please transcribe this text

[Assistant] You are so late. I've been waiting for you for half an hour.


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[Assistant] You are so late. I've been waiting for you for half an hour.


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[Assistant] You are so late. I've been waiting for you for half an hour.


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[Assistant] You only sleep five hours a day. Is that enough?


[User] Please transcribe this text

[Assistant] You only sleep five hours a day. Is that enough?


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[Assistant] You only sleep five hours a day. Is that enough?


[User] Please transcribe this text

[Assistant] My husband either watches his phone or plays games at home.


[User] Please transcribe this text

[Assistant] My husband either watches his phone or plays games at home.


[User] Please transcribe this text

[Assistant] My husband either watches his phone or plays games at home.


[User] Please transcribe this text

[Assistant] Let's get together sometime during the summer vacation.


[User] Please transcribe this text

[Assistant] Let's get together sometime during the summer vacation.


[User] Please transcribe this text

[Assistant] Let's get together sometime during the summer vacation.


[User] Please transcribe this text

[Assistant] Did you study English before you came to America?


[User] Please transcribe this text

[Assistant] Did you study English before you came to America?


[User] Please transcribe this text

[Assistant] Did you study English before you came to America?


[User] Please transcribe this text

[Assistant] Oh, your forehead is so hot. Do you have a fever?


[User] Please transcribe this text

[Assistant] Oh, your forehead is so hot. Do you have a fever?


[User] Please transcribe this text

[Assistant] Oh, your forehead is so hot. Do you have a fever?


[User] Please transcribe this text

[Assistant] I lived with my grandmother when I was a child. She brought me up.


[User] Please transcribe this text

[Assistant] I lived with my grandmother when I was a child. She brought me up.


[User] Please transcribe this text

[Assistant] I lived with my grandmother when I was a child. She brought me up.


[User] Please transcribe this text

[Assistant] The bus will arrive in five minutes. Get on.


[User] Please transcribe this text

[Assistant] The bus will arrive in five minutes. Get on.


[User] Please transcribe this text

[Assistant] The bus will arrive in five minutes. Get on.


[User] Please transcribe this text

[Assistant] My boyfriend works in the same unit as me, but he asked me to change my job.


[User] Please transcribe this text

[Assistant] My boyfriend works in the same unit as me, but he asked me to change my job.


[User] Please transcribe this text

[Assistant] My boyfriend works in the same unit as me, but he asked me to change my job.


[User] Please transcribe this text

[Assistant] Will you go back to your hometown this winter vacation?


[User] Please transcribe this text

[Assistant] Will you go back to your hometown this winter vacation?


[User] Please transcribe this text

[Assistant] Will you go back to your hometown this winter vacation?


[User] Please transcribe this text

[Assistant] What is the date today? What day is it today?


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[Assistant] What is the date today? What day is it today?


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[Assistant] What is the date today? What day is it today?


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[Assistant] For they have to study, study, and study.


[User] Please transcribe this text

[Assistant] For they have to study, study, and study.


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[Assistant] For they have to study, study, and study.


[User] Please transcribe this text

[Assistant] I bought another suit for my friend's wedding.


[User] Please transcribe this text

[Assistant] I bought another suit for my friend's wedding.


[User] Please transcribe this text

[Assistant] I bought two new chairs. Have a look.


[User] Please transcribe this text

[Assistant] I bought two new chairs. Have a look.


[User] Please transcribe this text

[Assistant] I bought two new chairs. Have a look.


[User] Please transcribe this text

[Assistant] I have nothing to do with this thing. Please do not find me again.


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[Assistant] I have nothing to do with this thing. Please do not find me again.


[User] Please transcribe this text

[Assistant] I have nothing to do with this thing. Please do not find me again.


[User] Please transcribe this text

[Assistant] Sorry, I can't go, for I have something tomorrow.


[User] Please transcribe this text

[Assistant] Sorry, I can't go, for I have something tomorrow.


[User] Please transcribe this text

[Assistant] Sorry, I can't go, for I have something tomorrow.


[User] Please transcribe this text

[Assistant] Is that picture hanging on the wall a new one?


[User] Please transcribe this text

[Assistant] Take the garbage down when you go downstairs later.


[User] Please transcribe this text

[Assistant] Take the garbage down when you go downstairs later.


[User] Please transcribe this text

[Assistant] Take the garbage down when you go downstairs later.


[User] Please transcribe this text

[Assistant] Throughout the United States, there is growing social awareness that sexual violence and harassment are far too common occurrences within our various institutions. Occurrences often without any accountability.


[User] Please transcribe this text

[Assistant] As a result, the MeToo movement is upon us and survivors everywhere are speaking out to demand change. Students have rallied against sexual assault on campus. Service members have demanded Congress reform the military.


[User] Please transcribe this text

[Assistant] And workers ranging from Hollywood stars to janitorial staff have called out sexual harassment in the workplace.


[User] Please transcribe this text

[Assistant] This is a tipping point. This is when a social movement can create lasting legal change, but only if we switch tactics. Instead of going by institution by institution, fighting for reform, it's time to go to the Constitution.


[User] Please transcribe this text

[Assistant] As it stands, the US Constitution denies fundamental protections to victims of gender violence, such as sexual assault, intimate partner violence and stalking.


[User] Please transcribe this text

[Assistant] That means that when a woman calls the police from her home, afraid that an intruder may attack her, she is not entitled to the state's protection.


[User] Please transcribe this text

[Assistant] Not only can the police fail to respond but she will be left without any legal remedy if preventable harm occurs as a result. How can this be?


[User] Please transcribe this text

[Assistant] It is because the state, theoretically, acts on behalf of all citizens collectively, not any one citizen individually.


[User] Please transcribe this text

[Assistant] The resulting constitutional flaw directly contradicts international law, which requires nation states to intervene and protect citizens against gender violence by private parties as a human right.


[User] Please transcribe this text

[Assistant] Instead of requiring intervention, our constitution leaves discretion. Discretion that states have used to discriminate systemically to deny countless victims any remedy.


[User] Please transcribe this text

[Assistant] Unlike what you may have seen on law and order SVU, justice is rare for victims of gender violence. And even in those rare cases where law enforcement is chosen to act, victims have no rights during the resulting criminal process.


[User] Please transcribe this text

[Assistant] You see, victims are not parties in a criminal case. Rather, they are witnesses, their bodies' evidence.


[User] Please transcribe this text

[Assistant] And the state has the discretion to dismiss criminal charges, enter lax plea deals and otherwise remove a victim's voice from the process, because again, a state theoretically


[User] Please transcribe this text

[Assistant] ...represents the interests of all citizens collectively and not any one citizen individually.


[User] Please transcribe this text

[Assistant] Despite this constitutional flaw, some victims of gender violence have found protections under federal civil rights statutes, such as Title IX.


[User] Please transcribe this text

[Assistant] Title IX is not just about sports, rather it prohibits all forms of sex discrimination, including sexual violence and harassment, within educational programs that accept federal funding.


[User] Please transcribe this text

[Assistant] It is Title IX that requires educational institutions to take reports of gender violence seriously or to suffer liability.


[User] Please transcribe this text

[Assistant] And through campus level proceedings, Title IX goes so far as to give victims equitable rights during the campus process, which means that victims can represent their own interests during proceedings, rather than relying on educational institutions to do so.


[User] Please transcribe this text

[Assistant] And that's really important, because educational institutions have historically swept gender violence under the rug, much like our criminal justice system does today.


[User] Please transcribe this text

[Assistant] So while civil rights protects some victims, we should want to protect all victims. Rather than going institution by institution fighting for reform on campus, in the military, in the workplace, it's time to go to the Constitution and pass the Equal Rights Amendment.


[User] Please transcribe this text

[Assistant] And much like Title IX on campus, that constitutional amendment could require states to intervene and address gender violence as a prohibited form of sex discrimination.


[User] Please transcribe this text

[Assistant] While the Equal Rights Amendment did not pass in the 1970s, it actually came within three states of doing so. And within the last year, at least one of those states has ratified the amendment, because we live in different political times.


[User] Please transcribe this text

[Assistant] So as a victim's rights attorney fighting to increase the prospect of justice for survivors across the country, and as a survivor myself, I'm not here to say time's up.


[User] Please transcribe this text

[Assistant] I'm here to say it's time. It's time for accountability to become the norm after gender violence. It's time to pass the Equal Rights Amendment.


[User] Please transcribe this text

[Assistant] Well, by golly, I can sure throw a rock at you! Where's a rock? Just let me find


[User] Please transcribe this text

[Assistant] I'm still quite young, you know. I may even tick out another book sometime-


[User] Please transcribe this text

[Assistant] But Zippy didn't. My brakes are fine, said Zippy. I don't need to check them.


[User] Please transcribe this text

[Assistant] Race cars never slow down. Yeaah, said Eddie. I won't check my brakes either.


[User] Please transcribe this text

[Assistant] Well hello and welcome to this English lesson where we're going to talk about the earth. We're going to talk about earth.


[User] Please transcribe this text

[Assistant] Notice I used a the and then I didn't use a the. You'll understand why in a moment. Uhm, but this is the fourth in a series of lessons. We did a lesson on air. We did a lesson on water. We did a lesson on fire.


[User] Please transcribe this text

[Assistant] Now we're doing a lesson on the earth. So I think this will be a fun lesson.


[User] Please transcribe this text

[Assistant] I don't know if you realize that when I do, uhm, the research to make the slides,


[User] Please transcribe this text

[Assistant] It's actually fun for me to do that. I think one of the reasons that I became a teacher is because I actually enjoy learning new things and putting lessons together and then teaching people like you. So welcome to this English lesson where we're going to talk about the earth.


[User] Please transcribe this text

[Assistant] So, Earth, you'll notice that I have two slides here.


[User] Please transcribe this text

[Assistant] I have earth and then I have a picture of someone putting a plant in dirt or soil.


[User] Please transcribe this text

[Assistant] So we refer to the ground as the earth, okay? So there is earth all around my house. The lawn grows in the earth that is on my property. But we also use the word earth to talk about the planet earth. So just a slightly different meaning for the word.


[User] Please transcribe this text

[Assistant] Again, you can talk about earth as basically all of the dirt that you see outside all of the soil, but you can also use the word earth to refer to the planet that we all live on.


[User] Please transcribe this text

[Assistant] Uhm, so hopefully you understand that distinction. We live on earth.


[User] Please transcribe this text

[Assistant] I'm not sure if you know what this person is doing, but they're riding a dirt bike. So, when you have dirt, you can buy a type of motorcycle that's called a dirt bike, uh, and you can use that, uh, to, uh, drive around in the dirt, and, uh, you get a little bit of dirt on you when you do it, but I'm sure it's quite fun.


[User] Please transcribe this text

[Assistant] So what is the difference between dirt and soil?


[User] Please transcribe this text

[Assistant] So, soil is the kind of dirt that you use when you want to grow things, okay? So, if you go to a farm, you could say, the field is full of dirt. It's a big field of dirt.


[User] Please transcribe this text

[Assistant] But you would probably more accurately say soil, okay? So I said the farmer worked up the dirt, the farmer has the field across from me ready to plant. It would probably be more accurate to say the soil is ready to be planted. Soil is the type of dirt


[User] Please transcribe this text

[Assistant] It's just really has a lot of nutrients. It has everything you need for plants to grow. So, soil is simply dirt that's really good for growing stuff. We have a lot of soil on our farm as well.


[User] Please transcribe this text

[Assistant] So the very top layer is called topsoil. You'll notice in this picture that the dirt close to the surface, the soil close to the surface, has a darker color to it.


[User] Please transcribe this text

[Assistant] This is actually called subsoil, but that's a different slide. The soil is a slightly different color, but everywhere you go in the world where they grow crops in fields, they'll talk about how much top soil they have.


[User] Please transcribe this text

[Assistant] There are parts of Canada where there is lots of topsoil and there are parts of Canada where there isn't very much topsoil. The more topsoil you have, the better your crops will grow. Uhm, my farm has an average amount of topsoil. Uhm, we also use the word land to almost


[User] Please transcribe this text

[Assistant] And we will simply refer to it as land and sometimes people will say I'm going to buy a piece of land and build a house. I'm going to buy some land and build a house and what they mean by that is they're going to buy


[User] Please transcribe this text

[Assistant] So when you talk about a farm, you can also use the word land. We sometimes call it farmland as well. But land is a word we use to refer to any place where there's no buildings.


[User] Please transcribe this text

[Assistant] And there's usually something growing there depending on where you live. If you can grow crops on a certain piece of land, we say it is arable.


[User] Please transcribe this text

[Assistant] So the amount of arable land in the world is finite. That means there's only a certain amount of it.


[User] Please transcribe this text

[Assistant] If you say, oh I have a piece of land for sale and someone says, and it's arable land, that means that you can grow crops on it.


[User] Please transcribe this text

[Assistant] There's a couple kinds of soil. I hope, by the way, I hope this lesson isn't too boring. I found it fascinating, but it is a very, uh, fairly specific topic. So hopefully you enjoy it. I know I always enjoy teaching them, but let's keep going.


[User] Please transcribe this text

[Assistant] There are a couple different kinds of soil, actually more than two, but I'm simply going to talk about clay and sand.


[User] Please transcribe this text

[Assistant] I know it might seem like sand is very fine, but clay is actually a very, very fine soil and it can get muddy very easily and it can hold lots of water when it gets wet.


[User] Please transcribe this text

[Assistant] The soil on my farm is mostly clay.


[User] Please transcribe this text

[Assistant] Another type of soil is a sandy soil or sand itself.


[User] Please transcribe this text

[Assistant] Sand doesn't hold water very well. In fact, water goes through sand very, very quickly. So, a couple of different kinds of soil. Clay soil and sandy soil. I didn't add the why there, but you can, I think you understand what I mean. And then I mentioned this earlier.


[User] Please transcribe this text

[Assistant] This is the top soil. And if you go down far enough, you have what's called the subsoil. The top soil is good for growing stuff. I think I'm covering up my mic. The subsoil is not great for growing stuff. And then if you go deep enough, you get to what's called bedrock.


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[Assistant] So in Canada, we have bedrock at a certain depth. If you dig far enough into the ground or if you drill far enough, you will hit bedrock.


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[Assistant] When they build large apartment buildings, they usually drill down so that they can hit bedrock so that the building has a solid foundation.


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[Assistant] Uh, where I live they often drill down to bedrock because there's water and natural gas available down there. So bedrock is if you go down far enough that you hit rock. If you've ever played the game Minecraft, I think if you dig far enough down you hit bedrock.


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[Assistant] Todd and Dave can confirm that for me. I haven't played Minecraft for a long time.


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[Assistant] Uhm, let me see here where I'm at. Yea, let's do two more and we'll do some questions. We can also buy soil. So if you need some earth to plant something in, you can go to the hardware store or almost any store at this time of year and buy a bag of soil.


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[Assistant] And that is a special kind of soil that you use to grow things in pots. So if you had some pots and you wanted to plant something and you know that things grow in good earth, you would go and buy some potting soil and put it in the potting soil in a pot.


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[Assistant] When dirt or soil gets a lot of water added to it when it rains or when even if you let your garden hose run by accident, you end up getting a lot of mud. Mud is simply dirt or soil or earth that has gotten very, very, very wet.


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[Assistant] So again, this is not a scientific lesson, so please don't, uh, get annoyed if I'm wrong, but to me, the crust of the earth


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[Assistant] The outside of the slice of bread or the outside of the loaf of bread is called the crust. The earth also has a crust and it's the top most thinnest layer. Let me make this slide bigger so you can see.


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[Assistant] The crust of the earth. So the top layer of rock and that little bit of dirt we would call the crust.


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[Assistant] Underneath the crust, you have what's called the mantle. So the mantle is the part of the earth between the crust


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[Assistant] And the core, which is actually my next slide. So the core of the earth is the hot center of the earth. So there's probably more layers than those three. Okay. But for the simplicity of this lesson, we have the crust of the earth or the earth's crust.


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[Assistant] The mantle of the earth or the earth's mantle, which is below the crust but above the core and then we have the earth's core or the core of the earth, which is the hot center of our planet.


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[Assistant] I'm going to talk a little bit about earth moving equipment.


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[Assistant] So earth moving equipment is the type of equipment that they use to move the earth around before they build things. So you have all kinds of different equipment that humans have invented to move the earth and it's called earth moving equipment or you might just call them earth movers. So we have what's called a greater


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[Assistant] A grader is a machine that they use. It has a big blade in the center.


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[Assistant] And they use this to kind of smooth out the dirt.


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[Assistant] When they make a place, when there's a place where they're going to put up a parking lot, they will often have a grader come in and it will make the, it will move all of the earth that it needs to in order to make things perfectly smooth so that they can build a parking lot.


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[Assistant] Sometimes we even see graders, we have dirt roads where I live and in the summer, um, late spring, early summer, a grader will come to level out the dirt road again because sometimes there's lots of potholes and puddles. We have a machine called a bulldozer


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[Assistant] A bulldozer is a tracked vehicle. Instead of wheels it has tracks.


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[Assistant] And it is a type of earth mover that's used to push dirt around.


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[Assistant] So it has a big blade on the front. A bulldozer is a very powerful machine that is used to move dirt simply by pushing it. Uhm, and I think because it has tracks, it can push really really hard because tires would spin really easily, but the tracks have better grip.


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[Assistant] Hey, thank you so much for becoming a member of the channel. That is very awesome of you. Thank you very much for that.


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[Assistant] Uhm, if you have watched any of my GeoGuessr live streams, which I do on my other YouTube channel,


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[Assistant] We almost always see an excavator somewhere. So an excavator is a machine with a big arm and bucket that can dig in the dirt. It can dig in the earth to make really deep holes. Usually when they are planning to build a house in Canada, an excavator will come.


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[Assistant] And we'll dig a hole with its big arm and big bucket. But yes, when we play GeoGuessr, I think almost every time I've played, I've seen an excavator and taught that vocabulary word. So this will be review for you.


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[Assistant] Uhm, I see Garav in the chat saying heavy machinery.


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[Assistant] We also call this heavy machinery. Thank you for that reminder. Okay. Uhm, and then Modag saying excavators here as well. Yes, they're everywhere. I think excavators, it's just a sign of the amount of construction in the world. We are constantly building things.


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[Assistant] Uhm, and we also have a type of, uh, earth mover or heavy machinery called a backhoe.


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[Assistant] A backhoe is called a backhoe because on the back it has an arm and a bucket for digging. Uhm, so a hoe in English is a tool you use in the garden and this looks a little bit like that tool.


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[Assistant] And then lastly we have what's called a dump truck. So a dump truck can be filled with dirt.


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[Assistant] Some of the more common earth moving equipment. A grater for leveling things. A bulldozer for pushing dirt and earth around. An excavator for digging holes. A backhoe for doing both. It's kind of, uh,


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[Assistant] Like a swiss army knife of earth moving machines. It has a loader on the front and a, um, a digger on the back.


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[Assistant] And then we have a dump truck for moving dirt and earth and stones and gravel and everything around. Uhm, these were some of my favorite vehicles as a child. I would always like seeing them go by on the road. I think a lot of kids like, uhm, dump trucks and, uh, excavators and all those kinds of things.


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[Assistant] Hey, so we mentioned earthworms earlier. Hey, art game, thank you so much for the super sticker. That is very awesome of you. Thank you. Uhm, earthworms, so,


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[Assistant] One of the reasons why from that big list that Natalia gave of all the things that live in the soil, one of the reasons I said earthworms were my favorite is because earthworms are a sign that the soil is really, really healthy.


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[Assistant] It's a sign that the soil is a good place to grow things. So Jen and I grow flowers, as many of you know.


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[Assistant] When we work up the soil, when we work up the earth, we're always happy to see earthworms because it means that the soil has lots of nutrients in it. It has everything you need for plants to grow well. So earthworms are my favorite thing to see in the soil.


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[Assistant] Uhm, we had a question about Earth Day. Earth Day takes place on April 22nd every year.


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[Assistant] Uh, and it is a day where we celebrate the earth. It's a day where people who, uhm, yeaah, I would say you might call them earth keepers. Uhm, that's a rare term, but someone who


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[Assistant] Really wants to keep the planet healthy, uhm, would celebrate Earth Day. Most places in the world, whether you are an environmentalist or not, whether you're someone who wants to make the Earth better or not, are usually, people are usually aware of Earth Day, a day when we celebrate the planet.


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[Assistant] So, sometimes the earth shakes and we call it an earthquake. Where I live in Ontario, Canada, we have minor earthquakes.


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[Assistant] Very rarely. So we have an earthquake every seven to ten years. And it's very, very minor.


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[Assistant] On the Richter scale, which is how they measure an earthquake, we're like the lowest possible. The last earthquake we had lasted about two seconds and it just felt a little strange.


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[Assistant] But in some places in the world, they have major earthquakes. Uh, earthquakes that are really high on the Richter scale.


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[Assistant] And they cause damage to buildings and they actually can cause people to become injured or to lose their life. So earthquakes are very, very serious thing in some parts of the world and of great concern.


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[Assistant] Uhm, luckily as humans get smarter,


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[Assistant] We build buildings that are better at withstanding earthquakes. We build buildings that are safer during an earthquake. So I think as time goes by, most of the world will become much safer. But even still now, earthquakes are very devastating, would be the best English word to use.


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[Assistant] So we had the word earthy, uh, come up in a question. When you say something is earthy, when you describe it as earthy, it has the colors of the earth, like the colors of dirt, the colors, like, or it smells a little bit like it. Okay. So there are, um, times when.


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[Assistant] Well, dirt itself smells earthy, okay? If you go outside right now and dig a hole with a shovel and smell the dirt, we would say it has an earthy smell.


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[Assistant] The best example would be, uhm, back in the 70s, there were people in North America called hippies, and they were very earthy people. I think that's probably the right way to describe them.


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[Assistant] But more we would use it to describe, uh, colors or tones or smells. So you could say, uhm, oh, I painted my, uh, my room, I painted my office, and I used a lot of earthy tones. I used a lot of earthy colors. So those would be like colors in the far picture, kind of that subtle look.


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[Assistant] Earthenware. So when you make things out of clay, primarily, usually the type of soil called clay, there are specific kinds of clay that are really good for making pots out of, and we say they're, they are earthenware pots.


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[Assistant] Basically meaning that they're made out of earth. That someone went and they dug up some clay.


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[Assistant] Um, I don't usually answer questions from the chat, but I see the question, hi Bob, do you have any dandelions in Canada? We have lots of dandelions in Russia, especially so far. Yes, we do. A lot of, in French, is it Don de Leon or do you guys say


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[Assistant] I'm not sure, but anyways, I'm sure if you saw my field right now, you would laugh at the amount of dandelions. People who


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[Assistant] You could say that we are citizens of the planet Earth. You could say that we are from the planet Earth. When you watch science fiction movies, people from Earth are often called Earthlings. So this here is an Earthling.


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[Assistant] Someone who is from the earth. Uhm, so definitely we have a name for ourselves. We are all earthlings. So sometimes you'll see an alien in a science fiction movie say earthling take me to your leader or something like that.


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[Assistant] Uh, Moise in the chat says, hi Bob, do you use fertilizer to grow flowers? Uh, Moise, we use the manure from our sheep and goats. So we compost our manure and we use that to fertilize our fields.


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[Assistant] Uhm, and Lolly says yes, Dont de Leon is Pisanlit.


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[Assistant] Let's talk a little bit about continents. I should mention that I did do a lesson on the Earth two years ago, and so the next three slides I think are a bit of a repeat. But the continents are the large land masses that we have divided the planet into.


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[Assistant] And they are the parts of the earth like North America, South America. Last time I talked about continents, there was an argument about how many there are.


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[Assistant] My understanding is that there are seven, but I think in some countries you learn that there are six or eight. So we should see in the chat in the comments below if people comment on that. But my understanding is that we have


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[Assistant] Uh, the seven continents that you see there. They are the large land masses that make up the planet Earth.


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[Assistant] We also have the northern hemisphere. The northern hemisphere is everything above the equator. The equator being the line, the imaginary line that divides the earth in half to north and south. So we have the northern hemisphere and the southern hemisphere.


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[Assistant] Sure you guessed that was coming next. So I live in the northern hemisphere. Some of you live in the southern hemisphere. In the northern hemisphere right now we're heading into summer.


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[Assistant] So funny, eh? It's getting warmer up here, but it's getting colder down there.


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[Assistant] We also have, like I mentioned, the thin line that goes around the earth called the equator. We also have the Tropic of Capricorn and the Tropic of Cancer, which are, when the earth tilts, they're the lines that


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[Assistant] Where this, don't quote, this is not a science lesson. I'm not talking about the Tropic of Cancer or the Tropic of Capricorn, but, uh, definitely the equator is the imaginary line.


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[Assistant] That is the exact center between the north, uh, the northern and southern hemispheres. If you want a science lesson, I'm sure there's other YouTube channels that will teach you more about the equator and the Tropic of Cancer and the Tropic of Capricorn.


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[Assistant] Uhm, at the very top of our planet, at the very top of the earth, is the North Pole.


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[Assistant] At the very bottom of the earth is the South Pole. The South Pole being in Antarctica.


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[Assistant] Uh, in the North Pole, I think being just in the middle of a huge ice flow, although I should research that. Again, this is not a science lesson. It's just an English lesson. Uhm,


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[Assistant] We also have this very curious, invisible thing around the planet called the Earth's magnetic field.


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[Assistant] The Earth's magnetic field is what allows us to navigate using a compass.


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[Assistant] A compass always points to the north magnetic pole, which is slightly off from the north pole, but close enough that it allows you to find out where north is.


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[Assistant] So a compass is a small round device with a magnetic needle in it and it will point to the magnetic north because the earth has a strong magnetic field.


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[Assistant] I don't think we fully understand the earth's magnetic field, but it is very, very important to many, many things.


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[Assistant] So the earth rotates, the earth rotates on its axis. Notice I changed the slide. So the earth rotates at a certain speed when the earth turns one full revolution.


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[Assistant] When the earth rotates one full revolution, we call it a day. So the earth is spinning very, very quickly and it's spinning on its axis. It's rotating on its axis. Notice I'm using different words here that mean the same thing and one full rotation of the earth equals one day, 24 hours. Pretty cool.


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[Assistant] Uhm, and yes, it spins on its axis. Now, interestingly enough,


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[Assistant] The axis is the center of the earth, the center of the earth from the north to the south, but the earth actually tilts on its axis back and forth.


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[Assistant] So sometimes Canada is closer to the sun for a few months and that's when we have summer and our days are longer and sometimes the earth is farther from the sun for a few months and that's when our days are shorter and we have winter. So that is the the tilt of the earth. Let me just check one thing here.


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[Assistant] So Earth has seasons because its axis is tilted. Earth's axis is always pointed in the same direction, so different parts of the Earth get the Sun's direct rays throughout the year.


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[Assistant] For example in summer the sun's rays hit that region more directly


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[Assistant] than any other time of year. So little explanation, mini science lesson about the axis.


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[Assistant] The earth orbits the sun, so it takes us, uhm, approximately 365 days.


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[Assistant] To orbit the sun and we call this a year. So the earth not only spins on its axis, but the earth as well is orbiting the sun and one complete orbit gives us a year.


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[Assistant] And then we also have, uhm, when the sun comes up, we say it's the sunrise, but if you are on the moon,


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[Assistant] You will see what's called Earthrise. So you will see the Earthrise above the horizon. So if I get up early enough, I can see the sunrise. So when I get up, it's dark. I didn't get up that early this morning. But if you get up early enough, you will see the sunrise. If you were on the moon and you got up early enough, you would see Earthrise.


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[Assistant] Uhm, you can see moonrise as well, I think, but again, this isn't a science lesson.


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[Assistant] Kate thought the teacher's lecture was dull, boring, and endless.


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[Assistant] Uuuh. I'm not really good at anything.


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[Assistant] Right, I mean we've developed, we've talked about amplifying stages, we've talked about compound stages, we've talked about single-ended differential conversion, talked about differential signalling to begin with, then we've talked about generating currents and biasing techniques, we've talked about driver stages,


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[Assistant] But now it's actually an interesting time because we can actually start building bigger systems with these. So we will continue doing that and we start to construct


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[Assistant] Now, there are other properties of op-amp. You want an op-amp, for example, to have reasonably high input impedance if it's used as a voltage amplifier, because you want it to be a good voltage sensor.


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[Assistant] You want it to have a reasonably low output impedance in general if you want to drive a load. Now it depends on what kind of load you want to drive. Sometimes you drive a


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[Assistant] Capacitive load, in that case you don't care really about the DC, the, the output DC resistance.


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[Assistant] If you're driving a resistive load, you do care about that output DC resistance, like when we were talking about the output stages, for example. So,


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[Assistant] The quick key question is that, what is the simplest block that does this? Isn't this just a single, single ended, differential to single ended converter?


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[Assistant] Let's construct it. Let's construct the simplest op-amp. Let's start with that. Well, the simplest op-amp would be a differential pair with an input.


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[Assistant] Differential. And then a differential to single-ended conversion using a current mirror, for example.


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[Assistant] Well, you can change the polarity. You can say this is gonna be gm vid over 2, because it was negative here. Uhm, so I changed the polarity of that.


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[Assistant] And this current is going to be reflected here, so this is going to be gm vid over 2. Both of these are injecting current into this node.


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[Assistant] Right, the two current sources, each injecting G and the ID over 2. What is the total resistance on that node?


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[Assistant] From that node to ground equivalent, from a differential perspective, from a differential perspective, this is a differential ground, so you see r o n here, r o p here, so your overall gain, of course, is a combination of these two, which can be easily seen to be g m, uhm, of n, these guys, uhm,


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[Assistant] Let's say for the sake of argument, then you get a gain that's basically in the range of 100, like that. That's actually pretty high. So let's make this actually 10, or, well, let's keep it 25, doesn't matter, you can get something. Doesn't matter. So you get something like in the order of 100, a gain of 100.


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[Assistant] From this. And again, we can do it more quantitatively. We'll do a lot more based on W over L's and all those things going forward. But just let's start with this. Let's say these are some of the numbers you're stuck. So your maximum gain you can get is 25 oh, 25 kilo ohms. Let's say parallel to 25 kilo ohms times 4 millisiemens. That's gonna be 50. Right?


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[Assistant] So the gain of this stage is going to disamplify, this is going to be 50. Now, you can say, is this a good op amp? Well, it depends. Good op amp for what?


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[Assistant] If you are trying to make something with a gain of a million, obviously this is not your, you're not there yet. We'll get there. But in steps.


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[Assistant] Right? So, it's 12.5 kiloohms. Is it a good thing? Well, depends on the load.


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[Assistant] If you're driving a resistive load, let's say I'm driving a 50 ohm load for the sake of argument. Let's say I was driving a 50 ohm load. Now is this a good op amp?


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[Assistant] What did change? What did just change? In parameters of the rpamp. Did its input impedance change? No.


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[Assistant] Which is gonna be 12.55 kilo ohms parallel 50 ohms, which is 50 ohms. Times 4 millisiemens, what's my gain? 0.2?


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[Assistant] It's not actually, it's not a good attenuator. A resistor is a better attenuator than that. Uh, cause it's non-linear too. But uhm, anyway. So, it's obviously not gonna work like that.


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[Assistant] But if I'm driving a high impedance load and all those things, we'll get to these things that do better than that in a sec, or in a little while.


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[Assistant] Even if you could, you can't put it on the chip. So what do we do, what do I put here?


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[Assistant] The transistor, right? So, you can put a current meter.


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[Assistant] For example, if you want to make it very independent of supply and temperature, and we'll make, do that, you can use all of those techniques that we use, we can use some of those reference currents that we generated. But, if we were really, really kind of like, wanted for something quick, looking for something quick and dirty, you can actually actually put an RF.


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[Assistant] Yeah, this will become supply dependent and everything, but yeah, I mean, this can generate a reference branch, replicate it here, use it as a reference current, and this is your most basic op-amp. Is it a good op-amp? No. But that's the most basic op-amp.


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[Assistant] Now, we need to make sure that we understand what this does and how this works. Because we are going to build up. A lot.


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[Assistant] Okay, so is it clear what everything in this very simplistic op-amp does? Right?


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[Assistant] What do these two guys do? It's a differential pair, right? It converts the differential input to a differential current, differential input voltage to a differential current. If you apply common mode, if this current source is a good current source, that output voltage, common mode is not going to change because the sum of them are forced to be constant, right?


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[Assistant] What does, what do these two do? It takes one of those currents, reflects it here, copies it here, so you can actually combine them into one node and you get a single-letter combination.


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[Assistant] What does this guy do? It uses the output resistance of a transistor to emulate a current source.


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[Assistant] Right? So if you're establishing, let's say, 100 microamps here, I want this to be like 2 microamps, 1 microamp, 5 microamps. Right?


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[Assistant] Cause like, otherwise I would be burning twice as much power and half of it is burning just like reference branch.


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[Assistant] If you make this L too small, your RO is gonna be small.


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[Assistant] If you make your L too large or W too large, the product of those things determines the capacitance.


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[Assistant] Uh, the gate capacitance of this thing, and that's going to determine your speed.


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[Assistant] Now, exactly what, depending on what you're trying to do and what speeds you're trying to achieve these different, you pick different places in this trade space. But again, that's where it is, trade-offs of the parameters. So again, right now, qualitatively. Okay.


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[Assistant] Yeah, you can put, for example, a source follower, right? You can take this here and use a source follower here.


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[Assistant] Now, if I do a source follower, I have limitations of the source follower, right? I have to worry about that, so let's make this another rail.


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[Assistant] 6 volt divided by 100, so it's like, uh, 60 milliamps, right?


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[Assistant] So I need to make this 60 milliamps if I were to use this kind of stage. Again, this is not the best stage to use for this, but as a starting point. Right?


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[Assistant] So, okay, so I make this 60mA. How do I make this 60mA? Well, I put, we put a transistor here that nominally


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[Assistant] Without dropping significant amount of delta Vgs, which means that probably should have a reasonably large W over L. Again, quantitatively. Right?


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[Assistant] Let's say this is designed so that the gain of this stage is not a limiting factor. We will calculate this going forward. But let's say this is not a limiting factor.


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[Assistant] The gain is gonna be still determined here, right? Now with this buffer stage that we put here, this follower stage that we put here, what is the gain now? The gain is back to that thing, right? Because now this is infinity from DC perspective.


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[Assistant] So that's the nice thing about MOSFETs, because the input impedances that they present, at least at DC, classically, it's large.


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[Assistant] Uhm, and you will see that this is not the case in bipolar when we make bipolar op-amps. So we have to do a lot more actually to get around that problem. Uhm, but we'll get there. So,


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[Assistant] Solutions, can you offer solutions if let's say gain of 50 is not enough? What do we do?


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[Assistant] You can use cascode for example, right? You can make this stage higher game. So what does that look like? Well...


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[Assistant] So you make each one of your stages a cascode. So let's say you have something like this, so this is your input stage, but now it needs to be cascode. So let's use it, use the current source temporarily here.


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[Assistant] And then you want to make a cascode stage. You make a common gate. Right?


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[Assistant] And if you are trying to get your single-ended output from this stage itself, you can do


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[Assistant] Something like that. So you have a cascode current mirror. These upper four transistors are a cascode current mirror, right?


[User] Please transcribe this text

[Assistant] It's just a better current meter. If this is a current meter, this top, this top two,


[User] Please transcribe this text

[Assistant] Matching is not the right word. It actually forces the two currents to be better matched or more equal.


[User] Please transcribe this text

[Assistant] So, alright, so that's plus VDD. You can go to negative VDD here.


[User] Please transcribe this text

[Assistant] Right, so again, the same deal as before. If you are in doubt, this is, this is gonna be VID over 2.


[User] Please transcribe this text

[Assistant] This is going to be negative VID over 2. And then this is going to be GM, let's say GM1, VID over 2. And this is going to be reflected here, GM1.


[User] Please transcribe this text

[Assistant] The total impedance on this node looking up, what do you see? Let's call this m1, m2, so let's call this 1.


[User] Please transcribe this text

[Assistant] Right, so what is the output resistance looking up?


[User] Please transcribe this text

[Assistant] Now, it's the intrinsic gain of this guy, times the output resistance of that, which is gonna be gm2, ro2, ro1. I mean, there's a plus one there.


[User] Please transcribe this text

[Assistant] You drop those things unless you're some, some degenerate cases.


[User] Please transcribe this text

[Assistant] Right? That you need to kind of like understand how you arrive at them, as opposed to the specific answer for the specific kind of solution. Because every time it looks different.


[User] Please transcribe this text

[Assistant] So we go from 25 kilo ohmish to times 100, this becomes 2.5 mega ohms, parallel to 2.5 mega ohms, times 4 millisiemens, uhm, it's eh,


[User] Please transcribe this text

[Assistant] Other than that current source, let's say we make this current source right. That's not the problem.


[User] Please transcribe this text

[Assistant] Exactly, there's nothing driving these gates. These gates are floating.


[User] Please transcribe this text

[Assistant] Right? So there's nothing biasing those gates. I have to come up with a way of biasing these gates. So how do we bias these things? There are thousands and one ways of doing that. But let's talk about some examples.


[User] Please transcribe this text

[Assistant] There are many different ways to do this. The one thing you want though, is that let me ask you this question. If you want to maximize your headroom, you brought up a good question of headroom, right? You mentioned that.


[User] Please transcribe this text

[Assistant] The question is that how should we, what is the ideal voltage this voltage can be? What's the best voltage I could set it at if I had a choice?


[User] Please transcribe this text

[Assistant] And I wanted to maximize my headroom, the maximum. So basically from this end, I want this voltage to go, these voltages, this voltage to be able to go as low as possible before any of these guys crunch it. For any of these two becomes basically, it goes into triode. Right? So when do these go to triode? Let's think about that. How low, what is the lowest this can go?


[User] Please transcribe this text

[Assistant] Before it goes into trial. The VDS can be as high as, as...


[User] Please transcribe this text

[Assistant] Ideally, I want this to be no more than another delta Vgs, right? That's the best case scenario. So if this is two delta Vgs's above here,


[User] Please transcribe this text

[Assistant] This means that this voltage has to be a VT plus 2 delta VGS above this point. Do you agree?


[User] Please transcribe this text

[Assistant] Because you need a VT plus delta VGS here, across the delta, across the gate source here, and you have a delta VGS here.


[User] Please transcribe this text

[Assistant] So this voltage, the best case scenario for it is VT plus 2 delta VGS. Well, this is microscopic.


[User] Please transcribe this text

[Assistant] That's what you want it to be at. How can you get vt plus 2 delta vgs? Well,


[User] Please transcribe this text

[Assistant] For example, if I have a diode connected transistor here,


[User] Please transcribe this text

[Assistant] To be, to produce this delta VGS, right?


[User] Please transcribe this text

[Assistant] So we need to provide a pathway for that. So with your permission, I take this out of here and put it on this side so we have room to play with things.


[User] Please transcribe this text

[Assistant] What's the best way to do that? Well, the easiest way is to put a current source up there.


[User] Please transcribe this text

[Assistant] Now you choose this current source to be a small fraction of this current source. Right? Because you don't want to be using all of that current to feed this thing. Right? So you can make it 1 one hundredth of that. Right? So whatever is this i tail, you make this i tail over 100.