阅读理解。

　　Can you imagine a world without the Internet?It's surprising to think about it．

　　Now, China has more than 162 million Internet users, according to the China Internet Network Information Centre．This is the second highest number of user in the world after the United States．Today, 66％of Chinese“netizens(网民)”are teenagers．“They spend about thirteen hours every week online,”said Qian Hulin, an Internet expert(专家)．Doctor Song in Beijing Xuanwu Hospital said about 14％ of Chinese netizens who are teens often lasted over ten hours to play online games．

　　The main reasons why teenagers surf the Web are to search for information, to communicate with others and to have fun．On the Internet, teenagers can find out almost anything．And surfing the Web can help students with their homework and widen their knowledge．

　　Li Dong, a teacher at No．41 Middle School in Shijiazhuang, likes her students to use the Internet．“When we talk in class, students who surf the Net usually know more background information than the others,”she said．

　　In addition, people can use the Internet to write letters or stories and send emails．Many teens keep in touch with their friends online．It is cheaper than phoning somebody far away and also much quicker．