Today, I’ll talk about going online.

We know that there are too many net bars around us. The Internet can make our lives interesting and enjoyable. Many of us like going online very much because we can learn how to use the computer and can get more information from the Internet. We can learn English. We can read some good newspapers and magazines. It can make us clever to play computer games. We can send e-mails to our friends quickly. We can chat freely online with our friends. It can help us get in touch with people from all over the world. But some students spend too much time in playing computer games and some stay in the net bars all day and all night. Some girls even get to have boyfriends or some boys get to have girlfriends online. They write too many letters to each other. It takes them too much time to chat online, so they do worse and worse in their lessons and they don’t study well any more. I think we mustn’t be online when it is time for us to study. We can do it in summer or winter holidays. I think we should go online with adults — our teachers or parents.

Fantastic You are good at using attributive clauses in your writing. The "struck" sentence is perfectly used. You'd better use "third person" in the first para. It's good to use the past tense in your writing.