Article in English: If you’re struggling with exactly how to say ‘thank you’ to someone, or what to say in a ‘thank you’ card, try using the who, what and when template. Start the ‘thank you’ process by making a list of everyone you need to send a ‘thank you’ card to.  For example, if it was your birthday and you received several gifts, write a list of everyone you received a gift from (and what they gave you).  This list should also include the names of anyone who helped you plan an event (e.g. birthday party). There are six basic parts to any personal ‘thank you’ note — the greeting, the expression of thanks, the details, the next time, the restatement, and the regards.   The Greeting is simple.  Start the ‘thank you’ note with the names of the people you are thanking.  If it’s a formal ‘thank you’ note, greet them formally (e.g. Dear Mr. Smith), if it’s family or a close friend, greet them informally (e.g. Hey Mom).  The Expression of Thanks is where you thank whomever for whatever they did.  The easiest thing to do is start this part with the words ‘thank you.’  But you can be more creative if you wish (e.g. It made my day when I opened my birthday gift from you).  The Details is where you get specific.  Adding specific details about why you’re thanking the person makes the note much more sincere and personal.  You might want to mention the specific gift you received, or what you spent gift money on, etc.  The Next Time is where you mention something about the next time you’ll see or speak to this person.  For example, if you’re sending a ‘thank you’ note to your grandparents and you’re going to see them shortly at Christmas, mention that.  The Restatement is where you wrap up your ‘thank you’ note with another message of thanks.  You can write another sentence (e.g. Thank you again for your generosity, I’m so very much looking forward to college and this money is going to help significantly) or you can simply say ‘thank you’ one more time.  The Regards is similar to the greeting except this time you’re signing your name. ...

Summary in Vietnamese:
Sử dụng lời ‘cảm ơn’ mẫu. Lập một danh sách những người mà bạn cần cảm ơn. Viết ra bạn biết ơn về việc gì. Lập kế hoạch khi nào sẽ gửi lời cảm ơn.