阅读理解。
During the day we work and play and at night we sleep. Our bodies rest while we sleep. In the morning
we are ready to work and play again. It is while we are asleep that our bodies grow most. When children feel
tired and angry, they usually need more sleep. We can get our lessons better, and we feel better, too, when
we have had plenty of rest. Boys and girls, eight or nine years old, need ten hours of sleep every night. Our
bodies need plenty of air when we sleep. If we do not get enough fresh air we wake up feeling tired. While in
bed we must not cover our heads. If we do, our lungs（肺）will not get enough fresh air. If we open our
windows at night we can have plenty of fresh air. Cool air is better than warm air. Boys and girls must get
plenty of sleep if they want to grow and be strong.
1. Our bodies grow most while we are ______.
[ ]
A. eating
B. playing
C. sleeping
D. exercising
2. Which is the best air for us? ______ air.
[ ]
A. Hot
B. Cool
C. Warm
D. Dry
3. What often makes us feel tired in the morning?
[ ]
A. Too much air.
B. Not enough fresh air.
C. Too much cold air.
D. Too much sleep.
4. How can you get plenty of fresh air at night? You can ______.
[ ]
A. open your windows
B. not sleep in bed
C. sleep ten hours
D. go to bed late
5. The writer is trying to tell boys and girls ______.
[ ]
A. to get their lessons better
B. not to cover their heads
C. how to go to bed
D. to get plenty of sleep