Section_ⅠWelcome_to_the_unit_&_Reading_-_Pre­reading

　　Do you know what you should be careful about when surfing the Net?

　　Using the web makes teenagers a target.Posting too much personal information for those millions to see can cause some big problems and can even invite danger to your life.

　　Not everyone on the Internet is who he or she says they are.Adults will sometimes post false photos and nice messages to gain trust.They use their false identity to get the personal information of others, such as home address, phone number, or school name.

　　Safety measures

　　If you set your information to "private"， which means that only the people you add under the "friend" can enter your page.You also shouldn't have any pictures of yourself on the site.The only material people can see is about your name, grade, and a list of hobbies.

　　Stay safe and have fun online

　　Experts say almost 90 percent of U．S.teenagers online.But not everyone knows how to surf the web in a smart way.With these tips, you can have fun, stay safe, and avoid danger.

　　·Pick a safe password.Make sure your password is something that other people won't be able to guess.

·Pick a safe user name.Make sure yours doesn't say too much about you, "Happy girl 13" is better than "Alice Waters 13"．Don't include your name, age, or where you are from.Never