The effects of air pollution on natural conditions have been a disturbing problem for many years. Some scientists hold the view that the air inside houses may be more dangerous than the air outside. It may even be one hundred times worse. Most scientists agree that every modern house has some kind of indoor pollution, which can cause a person to feel tired, to suffer eye pain, headache and other problems. Believe it or not, some pollutants can cause breathing diseases of blood and even cancer. What made us feel relieved is that there's growing concern about the problem now. It is true that when builders began constructing houses and offices they did not want to waste energy. they built buildings that prevented or limited the flow of air between inside and outside. For the same purpose, man-made building materials were employed to build houses, which are now known to let out some harmful gases. Facing the serious challenge, scientists have been searching for a way to handle the problem. To everyone's delight, they discovered a natural pollution control system for building--green plants, though they do not really know how plants control air pollution. Scientists suppose that a plant's leaves absorb or take in the pollutants and in exchange gives out oxygen through its leaves and tiny organizations on its roots. Therefore they recommend that all buildings should have one large plant or several small plants inside for every nine square meters of space. Because studies indicate that different plants absorb different chemicals, the most effective way to clean the air is to use different kinds of plants. In conclusion, having green plants inside your house can make it a prettier and healthier place. Why not try? Which of the following statements is TRUR? A) Outside air pollution is more harmful than the air inside. B) Scientists have discovered how plants control air pollution C) Indoor air pollution may cause diseases including cancer. D) Only large plants can absorb harmful gases indoors.
C
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Sayings  are quite common in spoken English. We don't normally put them in a composition or a letter. Sometimes it is helpful if you know what common proverbs mean. Here are a few examples. " Once bitten, twice shy." If a dog bites me, I shall be twice as careful in future when I see it. This proverb is also used to apply to many things and not only to dogs. For example, if you have been cheated at a shop, you will not go to the same shop again. "A bird in the hand is worth two in the bush." If I am a hunter, trying to catch birds, it is better to catch one than to see two birds in a bush but not able to catch them. Thus this means that what you have already got is better than the chance of being able to get something bigger in future. " Don't be a dog in a manger " means " Don't be selfish." In a stable  ,the manger is the place where the horse's food is put. Sometimes a dog will sleep in the manger and bark when a horse comes to get its food. The dog doesn't want to eat the horse's food in the manger but it will not let the horse eat it. " He who pays the piper calls the tune  ." A piper is a musician. The man who pays a musician can say what tunes the man will play. Thus this means that if a man provides the money for a plan, he can say how it will be carried out. "To pour oil on troubled waters" is to try to calm things down. Oil is lighter than water. If a ship is in trouble at sea, another ship may come to help it. The second ship can send small boats to rescue people. However, it may first pour oil on the sea to make the sea less rough. Mrs Lin wanted to buy a new dress. Her husband suggested that she buy it from a shop near their home. Mrs Lin disagreed because she had been cheated by that shop. So she said, " I won't go there again because   _   ." A) a bird in the hand is worth two in the bush B) he who pays the piper calls the tune C) once bitten, twice shy D) I don't want to be a dog in a manger
C
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I know my son seems very naughty. He cannot concentrate on reading, he makes silly mistakes in his homework or often fails his exams. Whenever such things happen, his teacher shouts,"Ask your parents to come here." And then I have to go with my tail between my legs to find out what's going on with my son and to listen to the teacher scold him. I really feel sorry for my son's mistakes and usually feel personally responsible. But I can't help feeling angry with him after a meeting with his teacher. Gradually, I have realized that anger will do him no good, and that actually he needs my help. On the other hand, I think that to educate our "little emperors ",there needs to be more understanding and cooperation between teachers and parents. While the teacher is scolding the child, the writer   _  . A) cuts in sometimes B) shouts at the student C) feels ashamed D) listens impatiently
C
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Scientists have transformed men's minds into avirtual woman's body in an experiment that could throw light upon how humans distinguish themselves form others. In a study at Barcelona University, men wore a virtual reality headset that allowed them to see and hear the world as a female character. When they looked down, they could even see their new body and clothes. The "body-swapping" effect was so convincing that the men's sense of self was transferred into the virtual woman, causing them to react to events in the virtual world they wereimmersed . "This work opens up another avenue for virtual reality, which is not just to transform your sense of place, but also your sense of self," said Mel Slater, "If you can temporarily give people the illusion that their bodies are different, then the evidence suggests it also affects their behavior and the way they think. They can have new experiences: a person who is thin can know what it is like to be fat. A man can have an experience of what it's like to be a woman." During the experiment, a "female" approached and hit the face of the character another man was playing. "Their reaction was immediate," said Slate. "They would take in a quick breath and maybeflinch . The more people reported being in the girl's body, the stronger physical reaction they had." But in all cases, the feeling was temporary and lasted only as long as the study. The study shows that our minds have a very fluid picture of our bodies. The research is expected to shed light on the puzzle of how our brain tells the difference between a part of our own body and something else in the wider world. Thus the work might improve the conditions for those who have experienced strokes by placing them in a world that helps them to use their bodies to the full again. Of the following statements, which we can't infer from the passage? A) Men in the experiment can temporarily have the wrong feeling that they are women. B) When hit, the men in the virtual world will react angrily to it. C) As soon as the experiment is finished, the men will return to the normal state D) Probably, this study can be applied to medical fields and benefit humans.

B
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