阅读理解。 There is an old English saying. It tells us that we must go to bed early and get up early in the morning. Then we shall be healthy. We shall also be rich and clever. This is true. The body must have enough sleep to be healthy. Children of young age should have ten hours' sleep every night. Children who do not have enough sleep cannot do their work well and they may not be healthy. The body also needs exercise. Walking, running, jumping and playing games are all exercise. Exercise keeps the body strong. Exercise also helps the blood to move around inside the body. It is very important. Our blood moves to all parts of our body. The head also needs blood. Exercise helps us to think better. 1. If we want to be healthy, we must ______. [     ] A. eat more B. sleep more C. play more D. go to bed early and get up early 2. Children of young age should have ______ hours' sleep every day. [     ] A. ten B. nine C. eleven D. twelve 3. If children don't have enough sleep, they will not ______. [     ] A. work well B. be clever and healthy C. eat well D. A and B 4. The body also needs ______. [     ] A. sports B. running C. exercise D. playing 5. Does exercise help us to think better? [     ] A. Yes, it does. B. No, it doesn't. C. No, it does. D. Yes, it deosn't.