阅读理解。

    The Internet has become part of teenagers' life.

    A news report on 3,375 students aged from 10 to 18 in seven Chinese cities found

that 38 per cent of them believe they use the Internet often.

    While most of them get useful information and use the Internet to help in their

studies, some are not using it in a good way. Many are playing online games too much.

A few even visit Web sites they should not look at. A middle school teacher from Beijing

warns that bad things can happen if young people spend too much time on the Internet.

She had a student who used to be good at school. But then he started visiting sex Web

sites. He went mad, cheated a girl and was taken away by the police.

    In order to help young people use the Internet in a good way, a textbook on good

Internet behavior has started to be used in some Shanghai middle schools this term. The

book uses real examples to teach students all about good ways of using the Internet. The

book gives useful advice such as it's good to read news or find helpful information to

study.

    Some students also make online friends. But if you are meeting a friend offline, make

sure your parents know. Teachers and parents all think the book is a very good idea.

This teacher said the book will be a guide for teens using the Internet. She believes it will

keep students away from bad sites. "Many students are using the Internet without guidance

from their parents," she said. "The book will teach students how to be a good person in

the online world."

1. The third paragraph mainly tells us that ______. [ ]

A. some students are not using the Internet correctly

B. all students in Beijing use the Internet to help their school work

C. a teacher in Beijing is worried about her students

D. some students visit sex Web sites

2. The textbook mainly tells us ______. [ ]

A. why we should use the Internet

B. not to visit sex Web sites

C. how to use the Internet correctly

D. how to get help from others

3. The writer advises the readers to ______. [ ]

A. let their parents know before visiting their online friends

B. not to make friends on line

C. read the textbook carefully

D. only read news on the Internet

4. From this passage we know that ______. [ ]

A. more and more students have given up visiting bad Web sites

B. schools and teacher begin to pay attention to students' use of the Internet

C. no more homework will be given in Shanghai

D. less and less information can be found on line