你受到笔友的来信：1.他喜欢玩电脑游戏，没时间写作业；2.因为晚上太晚睡，所以上课感觉很累；3.上课想认真听讲，但忍不住

I'm so glad to hear from you.I'm sorry to hear that you are in trouble now with your study.In my opinion, you should take some measures to help yourself.
Firstly,you must give up surfing online immediately if you still want to learn something. You can ask youself to listen carefully in class and finish your homework on time.
Secondly, you may need to turn to others for help for you may have a few problems on your study everyday.
Thirdly, you must force yourself to sleep early at night and get up on time the next day.
I hope these could be helpful to you.