Although the Internet of using the Internet has many useful utilities,it also has some negative effects.First of all,most teenagers use the Internet for negative purpose.They do nothing but play game,chitchat,spam and create dirty information on the Net.They waste their time,strength on it instead of focusing on studying.Secondly,the risk of spam on the Internet is inevitable and disturbs everybody.The Internet web and online advertisement contain age-inappropriate content .Unfortunately,it not only directly affects on children's characteristic and thought but it also makes them saucy.Finally,the attractively online game and the social network drive them get addicted to.Simulteaneously,spending too much time on it makes them passive and sluggish because of the lack of communicating skills in real life.In short,everything has two sides so it is neccessary for us to use the Internet for the right purposes.