Do you laugh every day? Scientists say that people laugh about 17 times a day. That is 21 laughter(笑声).
In India, there are __22__ laughter clubs. The people in these clubs（俱乐部） get together every morning. First they stretch their hands above their heads. Then they pretend to laugh. Soon everyone is laughing naturally. People say they feel good after __23__ together.
Scientists believe that laughter is good for you. __24__? For one thing, laughter is __25__ good exercise. When you laugh, you exercise many muscles in your body.
Scientists say that one hundred laughs are the same __26__ ten minutes of running. When you laugh, you __27___ breathe deeply. This makes you feel relaxed.
We know that people laugh __28__ in a group. Many scientists believe that we use laughter to make friends with _29__. Laughter helps us feel part of a group.
In English, people say that laughter is the best __30__. Some think that laughter helps sick people get well. Do you think so, too?
21. A. a lot B. many C. a lot of D. lot of
22. A. hundred of B. hundreds of C. hundred D. hundreds
23. A. laugh B. to laugh C. laughing D. laughed
24. A. Why B. What C. How D. When
25. A. a B. the C. / D. an
26. A. as B. like C. for D. of
27. A. too B. also C. either D. only
28. A. less often B. more often C. never D. hardly
29. A. anothers B. others C. other D. the other
30. A. magazine B. knowledge C. medicine D. friend
