As everyone knows, there are many 　16　 of transportation in the world, like bicycles, buses, ships, trains and 　17　 .

If you are in big  18　like Shanghai or Beijing, maybe you get to school   19  a subway or you have to 　20　 to school because you live in a mountain village. Here I am just trying to say something about　21　 .

Ten years　22　, bicycles were very　23　in most villages.  24　 family had one or two of bicycles. Children got to school by bicycle; 　25　 rode bicycles to go shopping. Then motorcycles (摩托车)   26  to become popular. People no longer rode bicycles because motorcycles ran   27  faster.  But now, in some countries，bicycles are highly suggested

  28  the main means of transportation. They think buses, cars and motorcycles pollute(污染) the air but bicycles   29  . So, to live a low-carbon life,   30  a bike is a good way.

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 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 get 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 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.

1.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.

2.Who else gives children some homework to do except their teachers?

　　   A. Their parents.　　　　　　　　　　　B. Other students.

　　   C. The children themselves.　　　　　　 D. Nobody else.

3.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.

4.What would happen to a student who often goes to bed late and gets up early?

　　   A. He would fall asleep in class.

B. He would do well in study.

　　   C. He would finish his homework fast.

D. He would have good health.

5.Which of the following is NOT true?

　　   A. Some students are so careless that they spend lots of time on their homework.

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

　　   C. Children should be given less homework.

   D. Schools and parents should take care of children.