1．不要沉湎于（be given to）上网以免影响生活和学习。
In my opinion，the Internet is helpful rather than harmful as someone else thinks. As is known to all，the Internet is playing a more and more important part in our daily life. On the Internet，we can read news at home and from abroad and get as much information as we can. We can send e - mails or make phone calls to our family as well as to our friends. We can also attend the net school，read many books and even teach ourselves English. We can also enjoy music，watch matches and play computer games on the Internet. We can even do shopping on line. Besides，we can improve our ability to operate the computer.
But we should not be given to the Internet，or we'll get our life and study destroyed. Besides，we should keep off the harmful websites. Anyhow，this doesn't prevent the Internet becoming our friend. We can't throw away the apple because of the core，can we？