根据短文内容，从A、B、C三个选项中选择一个最佳答案。
Everyone needs exercise. Do you often do exercise? We all 21 that exercise is good for people's health. Sports are a great way to exercise. They can help us to keep 22. Our parents and teachers need to exercise. After 23 long hours, exercise is relaxing for them. They can 24, go to swim and play ball games. They can do some easy exercise at home 25 yoga(瑜伽).
Exercise is useful to children, too. It can make 26 healthy and clever. Then we can do well in our 27.
Here are some easy ways to exercise. You can walk, run or only jump. Walking or 28 to school is also good exercise. And it's 29 for you to do that.
What's more, if you eat more but don't exercise, you can be 30. That's terrible, right? But you need to know what you are doing 31 why you are doing it.
Don't exercise too much. Try different sports and get one you 32 best. Then do it often. You can also exercise in the school 33 or at the gym. Exercise is fun. It can make you 34. You can exercise with friends and have a great time.
35 be sure to exercise every day. And then you can be happy, healthy and clever.
()21. A. talk B. teach C. know
()22. A. healthy B. big C. quiet
()23. A. studying B. working C. sleeping
()24. A. brush their teeth B. watch TV C. take a walk
()25. A. for B. with C. like
()26. A. her B. us C. him
()27. A. subjects B. sports C. habits
()28. A. playing B. driving C. riding
()29. A. difficult B. easy C. lazy
()30. A. fat B. important C. cool
()31. A. so B. and C. but
()32. A. ask B. join C. love
()33. A. library B. room C. club
()34. A. happy B. funny C. busy
()35. A. Never B. Sometimes C. Always

21.C 解析:句意:我们都知道锻炼对人们的健康有好处。talk 谈论;teach 教;know 知道。根据“exercise is good for people's health”并结合常识可知,这是我们都知道的事情。故选 C。
22.A 解析:句意:运动可以帮助我们保持健康。healthy 健康的;big 大的;quiet 安静的。根据“...exercise is good for people's health. Sports are a great way to exercise.”可知,运动可以帮助我们保持健康。故选 A。
23.B 解析:句意:在长时间工作之后,锻炼对他们来说是放松的。studying 学习;working 工作;sleeping 睡觉。根据“Our parents and teachers need to exercise.”可知,父母和老师应是长时间工作后需要放松。故选 B。
24.C 解析:句意:他们可以散步、游泳和打球。brush their teeth 刷牙;watch TV 看电视;take a walk 散步。根据“go to swim and play ball games”可知此处是与运动相关的内容。故选 C。
25.C 解析:句意:他们可以在家做一些简单的运动,比如瑜伽。for 为了;with 和;like 比如。根据“They can do some easy exercise at home 25 yoga(瑜伽).”可知,此处是对在家做的简单运动进行举例。故选 C。
26.B 解析:句意:它可以让我们健康、聪明。her 她;us 我们;him 他。根据“Then we can do well in our 27.”可推知,锻炼使我们健康、聪明。故选 B。
27.A 解析:句意:然后我们可以在学业上表现得很好。subjects 科目;sports 体育;habits 习惯。根据“It can make 26 healthy and clever. Then we can do well in our 27.”可推知,健康、聪明的人在学业上表现好。故选 A。
28.C 解析:句意:步行上学或骑车上学也是很好的锻炼。playing 玩耍;driving 驾驶;riding 骑行。根据“Walking or 28 to school is also good exercise.”并结合选项可知能起到锻炼作用的是骑车去上学。故选 C。
29.B 解析:句意:而且那样做对你来说是容易的。difficult 困难的;easy 容易的;lazy 懒惰的。根据“Here are some easy ways to exercise.”可知,此处也是“容易的”的意思。故选 B。
30.A 解析:句意:而且,如果你吃得多但不锻炼,你会变胖。fat 胖的;important 重要的;cool 酷的。根据“What's more, if you eat more but don't exercise”并结合常识可知,多吃少动会变胖。故选 A。
31.B 解析:句意:但你需要知道你在做什么以及为什么要那么做。so 因此;and 和;but 但是。此处用 and 连接并列的宾语从句。故选 B。
32.C 解析:句意:尝试不同的运动,找到你最喜欢的一项。ask 问;join 加入;love 爱。根据“Then do it often.”可知是要找出最喜欢的一项运动。故选 C。
33.C 解析:句意:你也可以在学校俱乐部或健身房里锻炼。library图书馆;room 房间;club 俱乐部。根据“You can also exercise in the school 33 or at the gym.”可推知,可以在学校俱乐部里锻炼。故选 C。
34.A 解析:句意:它可以让你快乐。happy 高兴的;funny 有趣的;busy 忙碌的。根据“You can exercise with friends and have a great time.”可知,锻炼能使人快乐。故选 A。
35.C 解析:句意:一定确保每天都锻炼。Never 从未;Sometimes 有时;Always 总是,一直。根据“35 be sure to exercise every day. And then you can be happy, healthy and clever.”可推知要确保每天都锻炼。故选 C。