In our industrialized and civilized society,our life usually depend on modern technology,like the computer,It's convenient for many aspects of our life,but the more popular ,the more critical voice there will be.some people said that it is harmful because of someone maybe indulge in on-line game or a virtual world in the site,especially among students,some of them abandended school work just resulted in computer game.
In my opinion,maybe computer have made some negative influence on people,but it had much more  virtue and made our life more comfortable and convinience.First and formost,email help us communicate with our friends easily.we don't need to go to postoffice to send letters to our friends or family members.it has saved our time and money that we bought envelops and stamps for letters.We can not only send words what we want to tell our friends ,but also  send pictures and videos ,even share music in the Email. 
What is more,we can also gain knowledge from the computer,for example,I had finished my graduated paper with the help of on-line reasouce in the university' library.when I prepared the paper,I must collecet material which can support my main point.there were so many books  in our library and it's too hard to look up all of them.My classmate suggested me that it'better to research material by use computer.then I found it's a wonderful suggestion,I had collected all reasouces that i want to use in my paper.Now there are even many on-line classes to help students learn kownledges.It does good to adolescence.
last,altough  computer exerted parts of negative influence to our society,if we live withour computer,we must go to postoffice to send letters,and we must buy something we need in the shop,we have to reasearch informatin for science paper or life use in the public library,there is no google and ebay.it's incrediable for us.I can not image that we don't have computer.It is one of the most important thing in our life.