please help for checking any grammer mistakes.Thanks

It is my composition and I have to hand in it tomorrow. Please help! Thank you

1.Your classmates, David/Susan who started smoking two years ago, quit smoking last month. Write a story about David/Susan. The following points may help you. ?How he/she started smoking ?What happened to him/her (his/her health, his/her relationship between people around him/her) when he/she started smoking ?Why he/she stopped smoking



Below here is a real-life story about my classmate, Susan who was my best friend. She always handed in homework on time two years ago. Everyone thought she was a good student but it is no longer fact.
One day, I saw Susan walking with her friends in the opposite street, and then I walked to her. One of her friends took out a pack of cigarette and asked us whether we wanted. I told him I didn’t smoke. Then he gave a cigarette to Susan and told her to try. Susan didn’t refused at that time, but asked him if he had a light. I was really shocked. She started smoking by peer pressure and kept smoking for her face. Then she was addicted to it. Susan’s health was turning bad when she started smoking. Once we ran together in the P.E. lesson, I discovered she ran slower than past. Furthermore, she got sick with influenza easier. I saw her looked tired all the time and she couldn’t pay any attention to the teacher during the lesson. Her school work went backward and teachers did not trust her as much as past. Classmates were distant with her for avoiding passive smoking. Her parents and I encouraged her in stopping smoking, but she didn’t take notice of it. Last month, the one who gave Susan a cigarette at first, his father quit smoking because of some serious diseases and he quit smoking too. He told Susan not to smoke anymore. She then pondered deeply over it. After that day, there was a speech about the harm of smoking and she found out she really got some of them. So she decided quit smoking.