The internet was set up in the 20th century. At that time computers were big and expensive. Later, the
computer becomes small and cheap. Thanks to (多亏) the internet, the world becomes smaller and smaller.
     A net friend is a man who talks to you online. You first talk to him in a chat room and then begin to know
him well. You never probably (可能) meet them, you have no way of knowing the real world around them.
So you mustn't meet or go out with them.
     QQ is a good way to chat and make friends. Now some young people don't often talk with their parents
or teachers, but they talk a lot with the old friends on QQ, but you must be careful about making net friends,
because you don't know the friends are good or bad on QQ.

1. When do people begin to use computer?
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2. What makes the world become smaller and smaller? 
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3. What is a good way to chat or make friends on the Internet? 
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4. Must we be careful about making Internet friends? 
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5. What is the best title (标题) for this passage? 
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