Spending two or three hours playing outdoors each day can reduce(减少)a child’s chance of becoming short-sighted（近视）,research shows . It challenges the belif that short-sightedness is caused by computer use , watching TV or reading in weak light .
Australian government researchers believe that sunlight is good for people’s eyes . They compared the vision （视力）and habits of 100 seven-year-old children in China and Australia .In all,30% of the Chinese children were short-sighted .This percentage was ten times higher than Australian children.
Both groups spent a similar amount of time reading, watching TV and playing computer games .However , the Australia children spent an average of two hours a day outdoors ,90 minutes more than the Chinese children.
Professor Ian Morgan said ,“Humans are naturally long-sighted ,but when people begin to go to school and spend little or no time outdoors ,the number of short-sighted peoplegets larger. We are also seeing more and more short-sighted children in cities all around the world –and the main reason may be that city children spend less time outdoors .
Daylight can be hundreds of times brighter than indoor light . But why does playing outside prevent us from becoming short-sighted ? Scientists believe that natural light has a special chemical（化学物质）which stops the eyeball from growing out of shape and prevents people from becoming short-sighted .
So go outdoors .It doesn’t matter if that time is spent having a picnic or playing sports .
根据材料内容选择最佳答案，并将其标号填入题前括号内。
【小题1】What can reduce a child's chance of becoming short-sighted according to the passage ?

"Spending as little as $5 a day on someone else can make you happier," the researchers from a team at the University（大学）of British Columbia and Harvard Business School reported.

    Their experiments on 600 volunteers in the US showed people were feeling happier when they spent money on others.

    The team asked their 600 volunteers about their income（收入），their daily costs, gifts for others and donations to charity. "No matter how much money each person made, those who spent money on others could get greater happiness than those who spent money only on themselves," Dunn said.

     Dunn's team also surveyed 16 workers at a company in Boston after they received an award of between $3,000 and $8,000. "Of course they felt happy after receiving the awards," they wrote in their report. "But when they gave the people in need $5, they were happier."

     "The findings showed that as little as $5 could be enough to produce happiness on a whole day," Dunn said.

1. There were ______ people in all who took part in the experiments.

2.The underlined word "experiments" means ______ in Chinese.

    A. 会议　　　　　　B. 表演             C. 实验             D. 化验

3.What does the passage mainly tell us?

    A. Money is not important for people.

    B. Money really can "buy" happiness if you spend it on others.

    C. We should try our best to give our money to more people in need.

    D. Spend all the money on others and you'll feel happier.

补全对话（每小题1分，共5分）

Dave：Can I ask you some questions, Sally?

Sally：Sure! What’s up?

Dave：   1. 

Sally：Yes, it’s a little far.

Dave：   2. 

Sally：First, I walk to the bus station and then I take the bus.

Dave：How long do you spend on the bus?

Sally：   3. 

Dave：Do you need to walk after you get off the bus?

Sally：   4. 

Dave：How many students in your class take the bus to school?

Sally：   5.

Dave：Thanks a lot.

The following four advertisements are from Star Evening News, Mar 8th, 2012

1.How much did you spend on four storybooks last week?

A. ＄12          B. ＄6          C. ＄4.8     D. ＄5

2.Which is the cheapest this week?

A. Jacket         B. Dictionary     C. Notebook   D. Storybook

3.Next week, which is cheaper than that of last week?

A. Storybook      B. Dictionary     C. Notebook   D.Jacket