完形填空。 Everyone must go to bed early and get up early, or we won't be healthier and clever. Is this true? Perhaps it is. The body must have 1 sleep. Children of your age need 2 sleep every day. If you don't go to bed early, you 3 enough sleep, then you can't think properly and can't do your work properly. You will not be clever. Some people go to bed late and get up late. This is not good 4 them. We must sleep at nine when it is dark. The dark help us 5 .When the daytime comes, we must get up. This is time for exercises. If you lack exercises, it becomes 6 . Exercises help a strong body. Exercises help the blood (血液) flow around 7 the body. This is very important. Blood takes food 8 all parts of our body, the brain (大脑) needs blood. We think 9 our brain. If we keep our body 10 and take exercises, we can think better. (     )1. A. enough (     )2. A. ten hours (     )3. A. will have (     )4. A. to (     )5. A. to sleep (     )6. A. to weak (     )7. A. outside (     )8. A. to (     )9. A. of (     )10. A. health B. many B. ten hours' B. can have B. for B. sleeping B. strong B. out of B. with B. about B. healthing C. some C. ten hour's C. won't have C. with C. slept C. weak C. into C. out of C. with C. healthy D. very D. ten-hours' D. have D. of D. to sleeping D. healthy D. inside D. from D. in D. doing