第四节 完形填空(共20小题,每小题1.5分,满分30分)

阅读下面短文,从短文后各题的A、B、C、D四个选项中,选出适合填入对应空白处的最佳选项,并在答题卡上将该选项涂黑。

     I used to live selfishly, I should admit. But one moment changed me.

     I was on my lunch break and had 26  the office to ger something to eat . On the way, I 27 a

Busker(街头艺人),with a hat in front of him. I had some 28 in my pocker, but I would not give them to him, thinking to myself he would 29 use the money to feed his addiction to drugs or alcohol. He 30 like that type-young and ragged. 31 what was I going to spend the money on ? Only to feed my addiction to Coca-Cola or chocolate! I then 32 I had no right to place myself above 33 just because he was busking.

I  34  and dropped all the coins into his 35, and he smiled at me, I watched for a while. As 36 as it sounds, I expected something  more to come from that moment—a feeling of 37 or satifaction, for example. But nothing happened 38 , I walked off. “It proved to be a waste of 39 ,”I thought.

On my way home at the end of the 40, I saw the busker again and he was 41 . I watched him pick up the hat and walk 42 a cafe counter. There he poured the 43 contents into a tin collecting 44 an earthquake fund-raising(募捐) event. He was busking for charity(慈善)!

Now I donate any 45 I have to charity tins and enjoy the feeling of giving.

26.  A. left           B. cleaned            C. prepared           D.searched   

27.  A. led           B. chose              C. saw               D. fooled     

28.  A. chocolates     B. coins               C. tins               D. drugs    

29.  A. almost        B. only               C. rather              D. still      

30.  A. acted         B. looked              C. sounded           D.smelt    

31.  A. Though        B. For               C. Therefor           D. But       

32.  A. declared       B. realized            C. expected           D. guessed    

33.  A. it            B. all                C. him                D. them      

34.  A. waited        B. followed           C. stopped            D. arrived     

35.  A. rag           B. hat                C. pocket             D. counter    

36.  A. selfish        B. awkward         C. innocent              D. special           

37.  A. happeiness     B. sadness          C. love                 D. hate                

38.  A. Disappointedly  B. Unfortunately    C. Coincidentally         D. Comfortably       

39.  A. words         B. effort           C. space                 D. money             

40.  A. moment       B. day              C. break                D. event             

41.  A. walking around  B. passing by        C. packing up           D. running off         

42.  A. around        B. in                C. behind              D. to                

43.A. chief            B. basic             C. actual               D. total             

44.A.by               B. for              C. on                  D. with              

45.A.work             B. time            C. energy               D.change            

Batteries can power anything from small sensors to large systems. While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves. University of Missouri(MU) researchers are developing a nuclear energy source that is smaller, lighter and more efficient.

“To provide enough power, we need certain methods with high energy density(密度)”,said Jae Kwon, assistant professor of electrical and computer engineering at MU. “The radioisotope(放射性同位素) battery can provide power density that is much higher than chemical batteries.”

Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various micro / nanoelectromechanical systems (M/NEMS). Although nuclear batteries can cause concerns, Kwon said they are safe.

“People hear the word ‘nuclear’ and think of something very dangerous,” he said, “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems.”

His new idea is not only in the battery’s size, but also in its semiconductor(半导体). Kwon’s battery uses a liquid semiconductor rather than a solid semiconductor.

“The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure(晶体结构) of the solid semiconductor,” Kwon said, “By using a liquid semiconductor, we believe we can minimize that problem.”

Together with J. David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery. In the future, they hope to increase the battery’s power, shrink its size and try with various other materials. Kwon said that battery could be thinner than the thickness of human hair.

1. Which of the following is true of Jae Kwon?

A. He teaches chemistry at MU. 

B. He developed a chemical battery.

C. He is working on a nuclear energy source.

D. He made a breakthrough in computer engineering.

2. Jae Kwon gave examples in Paragraph 4_________.

A. to show chemical batteries are widely applied.

B. to introduce nuclear batteries can be safely used.

C. to describe a nuclear-powered system.

D. to introduce various energy sources.

3. Liquid semiconductor is used to _________.

A. get rid of the radioactive waste  

B. test the power of nuclear batteries.

C. decrease the size of nuclear batteries

D. reduce the damage to lattice structure.

4. According to Jae Kwon, his nuclear battery _______.

A. uses a solid semiconductor       

B. will soon replace the present ones.

C. could be extremely thin          

D. has passed the final test.

5. The text is most probably a ________.

A. science news report        B. book review   

C. newspaper ad               D. science fiction story

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