PALO ALTO, California------"Switching off the television may help prevent children from getting fatter------ even if they do not change their diet or increase the amount they exercise," US researchers said last week.

　　A study of 192 third and fourth graders, generally aged eight and nine, found that children who cut the number of hours spent watching television gained nearly two pounds(0.9kg) less over a one-year period than those who did not change their television diet.

　　"The findings are important because they show that weight loss can only be the result of a reduction in television viewing and not any other activity," said Thomas Robinson, a pediatrician(儿科专家) at Stanford University.

　　"American children spend an average of more than four hours per day watching television and videos or playing video games, and rates of childhood being very fat have doubled over the past 20 years," Robinson said.

　　In the study, presented this week to the Pediatric Academic Societies‘ annual meeting in San Francisco, the researchers persuaded about 100 of the students to reduce their television viewing by one-quarter to one-third.

　　Children watching fewer hours of television showed a significantly smaller increase in waist size and had less body fat than other students who continued their normal television viewing, even though neither group ate a special diet or took part in any extra exercise.

　　"One explanation for the weight loss could be the children unstuck to the television may simply have been moving around more and burning off calories," Robinson said.

　　"Another reason might be due to eating fewer meals in front of the television. Some studies have suggested that eating in front of the TV encourages people to eat more," Robinson said.

1.The author tries to tell us in the first two paragraphs that ________.

2.According to the passage, the time American children usually spend on watching TV_____.

3. The time children spend on TV viewing every day is suggested to be about ________.

4.Which one of the following is right?

5.Why can watching TV increase kids’ weight according to the passage?

　　A. They usually eat more while watching TV.

　　B. They burn off fewer calories.

　　C. They change their diet while watching TV.

D. Both A and B.

　　The plan: turn Mars into a blue world with streams and green fields, and then fill it with creatures (生物) from the earth. This idea may sound like something from a science fiction (科幻小说), but it is actually being taken seriously by many researchers.

　　This suggested future for the “red planet” will be the main topic for discussion at an international conference hosted by NASA (美国宇航局) this week. Leading researchers as well as science fiction writers will attend the event. It comes as NASA is preparing a multi?billion?dollar Mars research programme. “Turning Mars into a little earth has long been a topic in science fiction,”said Dr Michael Meyer, NASA’s senior scientist for astrobiology (太空生物学). “Now, with scientists exploring the reality, we can ask what are the real possibilities of changing Mars.”

  Most scientists agree that Mars could be turned into a little earth, although much time and money would be needed to achieve this goal.

　　But many experts are shocked by the idea. “We are destroying our own world at an unbelievable speed and now we are talking about ruining another planet,” said Paul Murdin, of the Institute of Astronomy, Cambridge, UK. Over the past months, scientists have become increasingly confident they will find Martian life forms. Europe and America’s robot explorers have found proof that water, mixed with soil, exists in large amounts on the planet.

  In addition, two different groups of scientists announced on March 28 that they had found signs of methane (甲烷) in the Martian atmosphere (大气). The gas is a waste product of living creatures and could be produced by microbes (微生物) living in the red planet’s soil.

　　But scientists such as Dr Lisa Pratt, a biologist at Indiana University, say that these microbes will be put in danger by the little earth project. “Before we have even discovered if there is life on Mars, we are talking about carrying out projects that would destroy all these native lifeforms, all the strange microbes that we hope to find buried in the soil,” said Dr Pratt. This view is shared by Monica Grady, a planetary scientist at the Natural History Museum, London. “We cannot risk starting a global experiment that would wipe out the precious information we are looking for.” she said， “This is just wrong.”

5. The passage is about________.

A. a plan turning Mars into a little earth

B. the necessity of changing Mars

C. Mars supporting life

D. finding water in the Mars

6. Which of the following is NOT the reason why some scientists are against the plan?

A. The project would wipe out all the native lifeforms on the Mars.

B. The project will cost too much money and work.

C. We would ruin Mars.

D. We are destroying our own world at an unbelievable speed. 

7. We can infer from the passage that________.

A. water is a crucial factor for life

B. the project will have little effect on the native lifeforms supposed to live on the Mars

C. Monica Grady is in favour of carrying out the little earth project

D. the idea turning Mars into a little earth is nothing but a science fiction

8. Which of the following supports the conclusion of microbes living in the Mars’s soil?

A. Scientists found liquid water in the Mars.

B. Scientists found signs of methane in the Martian atmosphere.

C. Scientists found a lot of good soil on the Mars.

D. Scientists found some creatures living on the Mars.

Money spent on advertising is money spent as well as any I know of. It serves directly to bring about a rapid sale of goods at reasonable prices, so setting up a firm home market and making it possible to provide for export (出口) at good prices. By drawing attention to new ideas it helps greatly to raise standards of living. By helping to increase demand it causes an increased need for labour, and is therefore a nice way to fight unemployment. It lowers the costs of many services: without advertisements your daily newspaper would cost four times as much, the price of your television program would need to be doubled, and travel by bus or subway would cost more.

　　And perhaps most important of all, advertising provides a promise of reasonable value in the products and services you buy. Besides the fact that twenty-seven Acts of Parliament(国会)govern the terms of advertising, no regular advertiser dare produce anything that fails to live up to the promise of his advertisements. He might fool some people for a little while through misleading advertising. He will not do so for long, for the public has the good sense not to buy the poor goods more than once. If you see product frequently advertised, it is the proof I know that the product does what is promised for it, and that it has good value.

　　Advertising does more for the good of the public than any other force I can think of.

　　There is one more point I feel I ought to touch on. Recently I heard a well-known television person declared that he was against advertising because it persuades rather than informs. He was telling us the real difference. Of course advertising tries to persuade.

　　If its message were nothing but information, that would be difficult to get more people to buy, for even the choice of the colour of a shirt is a bit persuasive (有说服力的)--advertising would be so boring that no one would pay any attention. But perhaps that is what the well-known television person wants.

By the first sentence of the passage the writer means that ___.

　 A. he is fairly familiar with the cost of advertising

　 B. everybody knows well that advertising is a waste of money

　 C. advertising costs more money than everything else

　 D. money on advertising is worth spending

In the passage, which of the following is NOT included in the advantages of advertising?

　 A. Getting greater fame.              B. Providing more jobs.

　 C. Raising living standards.           D. Reducing newspaper cost.

The writer thinks that the well-known TV person is _____.

　 A. quite right in passing his judgment on advertising

　 B. interested in nothing but the buyers' attention

　 C. correct in telling the difference between persuasion and information

　 D. obviously unfair in his views on advertising

In the writer's opinion, ________.

　 A. advertising can seldom bring material interest to man by providing information

　 B. advertising informs people of new ideas rather than wins them over

　 C. there is nothing wrong with advertising in persuading the buyer

　 D. the buyer is not interested in getting information from an advertisement