题目内容：

In the quest for better health, many people turn to doctors, self help books or herbal supplements. But they overlook a powerful weapon that could help them fight illness and depression, speed recovery, slow aging and prolong life: their friends.

Researchers are only now starting to pay attention to the importance of friendship and social networks in overall health. A 10-year Australian study found that older people with a large circle of friends were 22 percent less likely to die during the study period than those with fewer friends. A large 2007 study showed an increase of nearly 60 percent in the risk for obesity among people whose friends gained weight. And last year, Harvard researchers reported that strong social ties could promote brain health as we age.

“In general, the role of friendship in our lives isn’ t well appreciated,” said Rebecca G. Adams, a professor of sociology at the University of North Carolina, Greensboro. “There are a lot of things on families and marriage, but very little on friendship. It baffles me. Friendship has a bigger impact on our psychological well being than family relationships.”

Bella DePaulo, a visiting psychology professor at the University of California, Santa Barbara, whose work focuses on single people and friendships, notes that in many studies, friendship has an even greater effect on health than a spouse or a family member.

It isn’ t entirely clear why friendship has such a big effect. It may be because people with strong social ties also have better access to health services and care. Beyond that, however, friendship clearly has a profound psychological effect. People with strong friendships are less likely than others to get colds, perhaps because they have lower stress levels.

Last year, researchers studied 34 students at the University of Virginia, taking them to the base of a steep hill and fitting them with a weighted backpack. They were then asked to estimate the steepness of the hill. Some participants stood next to friends during the exercise, while others were alone.

The students who stood with friends gave lower estimates of the steepness of the hill. And the longer the friends had known each other, the less steep the hill appeared.

“People with stronger friendship networks feel like there is someone they can turn to，” said Karen A．Roberto, director of the center for gerontology (老年医学) at Virginia Tech.“ Friendship is an undervalued resource. The consistent message of these studies is that friends make your life better.”

1.What’ s the main idea of the passage?

A. People should make friends as many as possible.

B. Friendships do great good to human health.

C. People with friends have optimistic attitude.

D. Several studies have been done on friendships.

2.Which of the following is true?

A. People haven’t attached importance to friendships.

B. A friend can replace doctors and selfhelp books.

C. People with many friends may have higher stress levels.

D. People who have friends tend to be fat.

3.The author mentioned the study in the last three paragraphs to indicate that ________.

A. students should climb the steep hill with friends

B. it takes a long time to make friends

C. a friend in need is a friend indeed

D. people accompanied by friends remain optimistic in the face of difficulty

4.In Paragraph 2 the author aims to tell us ________.

A. friendship has a strong physical effect on people’s health

B. we cannot be too careful when making friends

C. older people are likely to have fewer friends

D. 60 percent of the people without friends will become fat when they get old

5.According to Karen A. Roberto, ________.

A. the effect of friendships is overvalued

B. studies on friendships make our life better

C. friends are more important than family members

D. friends can help each other when faced with problems