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　　●Some web sites are wonderful, but some the teenagers should stay away．

　　Caution(警告)：Web sites sometimes ask you for information about yourself before you enter．Never type any information about yourself．And also remember not to download anything unless you’re quite sure it is from a safe place．

　　Some teenagers have their own web sites．That’s good．But if you post something on the web, be sure not to send your home address, telephone number, or photograph．If you do want to keep in touch with someone, just give an E-mail address．

　　●Chat rooms(聊天室)are probably the most dangerous places on the Internet．

　　Caution：It can be wonderful to get together with someone you meet here, but remember-people are not always who they seem to be on the Internet．Never give out personal information, and never ask for a face-to-face meeting without first talking with your parents．

　　●Instant(即时的)messaging(IM)has become popular among teenagers．You type a message and then click“send”．The message will soon be on another person’s screen(屏幕)．You can send instant messages on computers and cell phones．

　　Caution：Be sure you know who you are“Iming”with, and know that anything you type could be sent to the right people．Or don’t send any information about yourself to others．And be especially careful about using cameras during an IM meeting．You don’t have to answer any messages that make you feel uncomfortable．

　　●Now, people and companies are using Emails to send out messages to thousands of people at a time, encouraging them to buy something, do something, or visit a web site．

　　Caution：In general, it’s best not to answer junk mail(邮寄宣传品)or mail from someone you don’t know．If you answer with your personal information, for example, your home address to the sender, that information can be used to send you more junk mails or get you on even more lists．

1．Is it good to send your home address while posting on line?

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2．Which is the better way to keep in touch with someone, giving an email address or sending your phone number?

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3．What may be the most dangerous places on the Internet according to the passage?

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4．How can you send instant messages？

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5．What does the writer think is the most important thing on using the Internet?

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