As everybody knows,Internet is a very important part of our But for the teenagers,it's not always Internet is a double-edged There is lots of information on the ISo it's a very helpful tool for students to get information swiftly and However, some information is good and some may be So for the teenagers,it's important to find out the good things and keep the bad things But most teenagers haven't got such good self-So,if someone young is surfing on the Internet,it's a good idea to use the"Green Dam"