答案：
Recently I have found many of my classmates feel sleepy and tired during class. It’s obvious that they stay up too late studying or doing something else at night. Lack of sleep does great harm to us students. For one thing, we can’t concentrate in class if we don’t get enough sleep. As a result, our studies will be affected. For another, it may lead to problems like obesity and heart trouble. Moreover, we may get angry and impatient easily due to lack of sleep. Therefore, getting enough sleep is extremely important. To do so, we need to form a good sleeping habit. Go to bed early and get up early. Then our lives will greatly improve.
本文是一篇半开放性的作文。所述话题是中学生比较熟悉的，但所给要点比较散，尤其是在合理的建议方面需要考生做适当的发挥。在写作时，请注意使用高级词汇和合理的连接词，让文章更有层次。