题目内容：

    A study showed that fat was socially catching among friends. People were actually making one another gain and, sometimes, lose weight. The finding has been proved in other populations. So how does friends’ body weight affect each other? One way is imitation (模仿). Brain scans show that when you watch someone else eat or run, your brain activity is the same as if you were eating or running yourself, causing you to do the same things.

People in experiments seated next to heavy eaters would eat more than those seated next to light eaters. Social examples also play a role: If your friend gains weight, you might become less willing to go to the gym because your friend’s example showed you that weight gain isn’t the end of the world. She’s heavier but still the same person you know and love. And now that 66 percent of the American population is overweight, that’s a pretty well-fixed social example.

Happily, this effect could be turned up side down if people worked to create an opposite social example—weight loss can affect each other just as easily as weight gain if you form the fat-fighting habits, starting a running club including friends of friends so that you’re making close friends with more exercisers. You can also make healthier food choices and eat with greater self-control. If you give up the fries and eat more vegetables, your friends are more likely to make the same choices.

If you’re thinking those sound like a lot of work, maybe it would just be easier to ditch friends who gain weight to stop them from affecting you. People who kept away from a fat friend didn’t lose weight, possibly because the cost of losing a friend stopped weight-loss efforts.

1.What will people in the experiments do if they eat with heavy eaters?

A. Hate them. B. Leave them.

C. Follow them. D. Lose weight.

2.How might people respond to their fat friends according to the text?

A. Go to the gym with them often.

B. Think nothing of becoming fat.

C. Warn them the danger.

D. Like them better.

3.What can you do to make good use of the discovery?

A. Set a good example for your friends.

B. Make up your mind to make more friends.

C. Set up health club as a business.

D. Drink more water.

4.What does the underlined word “ditch” in the last paragraph mean?

A. Depend on. B. Relieve in.

C. Watch over. D. Give up.