In China, more and more middle school students are getting shorter sleeping time than before. Most students sleep less than nine hours every night, because they have much homework to do. Some homework is given(被给出) by their teachers, and some by their parents. Also, some students don't know how to save time. They are not careful enough while they do their homework, so it takes them a lot of time. Some students spend too much time watching TV or playing computer games. They stay up (熬夜) very late. Some students have to get up early every morning on weekdays to go to school on time by bus or by bike. It can be a long way from home to school.

Schools and parents should cut down (减少)some of the homework so that our children can enjoy more than nine hours of sleep every night for their health. For children, we should make best use of our time. When we have enough time for sleeping, we will find it much better for both our study and health.

根据短文内容，选择最佳答案，并在答题卷上按要求作答。

71.What makes most students sleep less than nine hours every night?

　 A. Watching TV.　　　　　　　　　　 B. Playing computer games.

　 C. Doing their homework.　　　　　　 D. Doing housework.

72.Who else gives children some homework to do？

A. Their parents.　　　　　　　　　　　B. Other students.

C. The children themselves.　　　　　　 D. Nobody else.

73. How many hours of sleep is good for students' health?

A. Less than 9 hours.　　　　　　　　　 B. Over 9 hours.　　

C. Only 9 hours.　　　　　　　　 　　 D. 8 hours.

74. Sleeping enough is much better for 　　　　　　　　 .

　 A. our study 　　　　　　　 B. nobody

C. our health　　　　　　　　 D. both our study and health

75.Which of the following is NOT true?

　 A. Students should have enough time for sleeping.

　 B. All the students should stay up late for their homework.

　 C. Children should be given less homework.

　 D. Schools and parents should take care of children.