Even plant can run a fever, especially when they’re under attack by insects or disease. But unlike human, plants can have their temperature taken from 3, 000 feet away straight up. A decade ago, adopting the infrared (红外线)scanning technology developed for military purposes and other satellites, physicist Stephen Paley came up with a quick way to take the temperature of crops to determine which ones are under stress. The goal was to let farmers precisely target pesticide (杀虫剂)spraying rather than rain poison on a whole field, which invariably includes plants that don’t have pest (害虫)problems.

  Even better, Paley’s Remote Scanning Services Company could detect crop problems before they became visible to the eye. Mounted on a plane flown at 3, 000 feet at night, an infrared scanner measured the heat emitted by crops. The data were transformed into a color-coded map showing where plants were running“fevers”. Farmers could then spot-spray, using 50 to 70 percent less pesticide than they otherwise would.

  The bad news is that Paley’s company closed down in 1984, after only three years. Farmers resisted the new technology and long - term backers were hard to find. But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get back into operation. Agriculture experts have no doubt the technology works. “This technique can be used on 75 percent of agricultural land in the United States, ” says George Oerther of Texas A & M. Ray Jackson , who recently retired from the Department of Agriculture, thinks remote infrared crop scanning could be adopted by the end of the decade. But only ff Paley finds the financial backing which he failed to obtain 10 years ago.

Plants will emit an increased amount of heat when they are______________.

A. sprayed with pesticides          

B. facing an infrared scanner

C. in poor physical condition        

D. exposed to excessive sun rays

In order to apply pesticide spraying precisely, we can use infrared scanning to____________.

A. estimate the damage to the crops  

B. measure the size of the affected area

C. draw a color-coded map         

D. locate the problem area

Farmers can save a considerable amount of pesticide by______________.

A. resorting to spot-spraying       

B. consulting infrared scanning experts

C. transforming poisoned rain      

D. detecting crop problems at an early stage

The application of infrared scanning technology to agriculture met with some difficulties

_______________.

A. the lack of official support      

B. its high cost

C. the lack of financial support      

D. its failure to help increase production

Infrared scanning technology may be brought back into operation because of_____________.

  A. the desire of farmers to improve the quality of their produce

  B. growing concern about the excessive use of pesticides on crops

  C. the forceful promotion by the Department of Agriculture

  D. full support from agricultural experts                  

阅读下面短文,按照句子结构的语法性和上下文连贯的要求,在空格处填入一个适当的词或使用括号中词语的正确形式填空,并将答案填写在答题卡标号为16—25的相应位置上。  In order to know a foreign language thoroughly, four things are necessary. Firstly, we must understand the language when we hear    16.           spoken. Secondly, we must be able to speak it ourselves correctly with confidence and without hesitation.    17.                , we must be able to read the language, and fourthly, we must be able to write it. We must be able to make sentences that are grammatically correct.

There is no easy way to success   18.            language learning.          19.                    good memory is a great help, but it is not enough only    20.                   (memorize) rules from a grammar book. It is not much use learning by heart long lists of words and   21.                 meanings, studying the dictionary and so on. We must learn by using the language. 22           .         we are satisfied with only a few rules we have memorized, we are not really learning the language. “Learn through use” is a good piece of   23.            (advise) for those   24.           are studying a new language. Practice is important. We must practise speaking and   25.            (write) the language whenever we can.

For the second time in three years, Norway's Robert Sorlie delivered a brave performance to win sled-dog racing's toughest contest—the Iditarod. The 47-year-old firefighter crossed the finish line in Nome, Alaska, at 8:39 a.m. local time Wednesday morning.

"It feels good to be here," he declared, after passing the finish line. "I'm ready for breakfast."

Frosty temperatures, rough land, and exhaustion couldn't break the musher (赶狗拉雪撬的人), who completed the race in 9 days, 18 hours, 39 minutes, and 31 seconds. Runner-up Ed Iten finished 34 minutes later, and defending champ Mitch Seavey finished third.

Sorlie took his first lead at the 365-mile mark, but fell into second place halfway through the race. With 500 miles to go, he regained the lead for good.

Iditarod officials rewarded Sorlie with a generous prize of $72,066 and a new truck. But even more exciting for the winner was the historic nature of his ride. By winning this year's race, Sorlie joins a best group of mushers, becoming only the sixth person to win the Iditarod more than once.

After winning several major long-distance races in Europe, Sorlie made his Iditarod first appearance in 2002, finishing in ninth place. A year later, he returned to take on the Alaskan wilderness once again, and won.

Iditarod: A Quick History

Since 1973, the world's top competitors have gathered in Alaska to undertake the Iditarod's 1,150-mile trail, which stretches from Anchorage to Nome.

The race commemorates(纪念)a group of courageous mushers and dogs. In 1925, they traveled across part of the Idit trail to deliver serum(血清)to save sick children in Nome.

How many times has Robert Sorlie won the Iditarod?

       A.Once.     B.Twice.     C.Three times.          D.Several times.

How long did it take Ed Iten to finish the race?

       A.9 days, 19 hours, 13 minutes, and 31 seconds.

       B.9 days, 18 hours, 5 minutes, and 31 seconds.

       C.9 days, 18 hours, 39 minutes, and 31 seconds.

       D.9 days, 18 hours, 13 minutes, and 31 seconds.

This win was very important for Sorlie because he could _____.

       A.get the generous prize of $72,066 and a new truck

       B.get a chance to race in Europe

       C.join a best group of mushers

       D.save sick children in Nome

How long has the Iditarod been held?

       A.Only 3 years.   B.Over 100 years.       C.About 80 years.       D.Over 20 years.

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