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科目: 来源: 题型:阅读理解

  Far from the land of Antarctica(南极洲), a huge shelf of ice meets the ocean. At the underside of the shelf there lives a small fish, the Antarctic cod.

       For forty years scientists have been curious about that fish. How does it live where most fish would freeze to death? It must have some secret. The Antarctic is not a comfortable place to work and research has been slow. Now it seems we have an answer.

       Research was begun by cutting holes in the ice and catching the fish. Scientists studied the fish’s blood and measured its freezing point.

       The fish were taken from seawater that had a temperature of -1.88℃ and many tiny pieces of ice floating in it. The blood of the fish did not begin to freeze until its temperature was lowered to -2.05℃. That small difference is enough for the fish to live at the freezing temperature of the ice-salt mixture.

       The scientists’ next research job was clear: Find out what in the fish’s blood kept it from freezing. Their search led to some really strange thing made up of a protein(蛋白质) never before seen in the blood of a fish. When it was removed, the blood froze at seawater temperature. When it was put back, the blood again had its antifreeze quality and a lowered freezing point.

       Study showed that it is an unusual kind of protein. It has many small sugar molecules(分子) held in special positions within each big protein molecule. Because of its sugar content. It is called a glycoprotein. So it has come to be called the antifreeze fish glycoprotein. Or AFGP.

 

41. What is the text mainly about?

   A. The terrible conditions in the Antarctic.

   B. A special fish living in freezing waters.

   C. The ice shelf around Antarctica.

   D. Protection of the Antarctic cod.

42. Why can the Antarctic cod live at the freezing temperature?

   A. The seawater has a temperature of -1.88℃.

   B. It loves to live in the ice-salt mixture.

   C. A special protein keeps it from freezing.

   D. Its blood has a temperature lower than -2.05℃.

43. What does the underlined word “it” in Paragraph 5 refer to?

   A. A type of ice-salt mixture.          B. A newly found protein.

   C. Fish blood.                               D. Sugar molecule.

44. What does “glycol-” in the underlined word “glycoprotein” in the last paragraph mean?

   A. sugar                  B. ice                    C. blood                D. molecule

 

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科目: 来源: 题型:阅读理解

After the birth of my second child, I got a job at a restaurant. Having worked with an experienced  21  for a few days, I was   22  to wait tables on my own. All went  23   that first week. When Saturday night came, I was luckily  24  the tables not far from the kitchen.   25   , I still felt a little hard to carry the heavy trays (托盘)。

    Before I knew it, the  26  was full of people. I moved slowly,   27  every step. I remember how  28   I was when I saw the tray stand near the tables, it looked different from the one I was  29   on. It had nice handles (手柄),which made it  30   to move around. I was pleased with everything and began to  31  I was a natural at this job.

    Then, an old man came to me and said, “Excuse me, dear, my wife and I loved __32  you work. It seems your tray stand has been very  33  to you, but we are getting ready to  34   now, and my wife needs her  35  back.”

    At first his   36  did not get across. “What was he talking about!” Then I got it. I had set my trays on his wife’s orthopedic walker (助步器). I stood frozen as ice, but my face was  37  . I wanted to get into a hole and  38  .

    Since then, I have learned from many mistakes such as the one I just   39   , I have learned to be more  40  and not to be too sure of myself.

 

21. A. manager    

B. assistant    

C. cook     

D. waitress

22. A. promised   

B. invited      

C. allowed  

D. advised

23. A. well       

B. quickly     

C. safely    

D. wrong

24. A. left        

B. given      

C. brought   

D. shown

25. A. Therefore    

B. However   

C. Otherwise 

D. Finally

26. A. kitchen     

B. street      

C. restaurant  

D. table

27. A. minding    

B. changing   

C. taking     

D. saving

28. A. angry      

B. calm      

C. sad        

D. happy

29. A. fixed       

B. trained    

C. loaded     

D. waited

30. A. slower      

B. lighter    

C. quieter     

D. easier

31. A. believe     

B. agree      

C. regret      

D. pretend

32. A. letting      

B. making    

C. watching    

D. having

33. A. useful       

B. familiar    

C. unusual    

D. interesting

34. A. rest        

B. order      

C. eat         

D. leave

35. A. bag        

B. walker     

C. tray        

D. coat

36. A. idea        

B. praise     

C. message     

D. need

37. A. cold         

B. full of joy  

C. pale        

D. on fire

38. A. lie         

B. hide       

C. defend      

D. stay

39. A. repeated    

B. discovered  

C. corrected    

D. described

40. A. careful      

B. patient     

C. honest     

D. practical

 

 

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The careless driver is _________ for the traffic accident that __________ yesterday.

      A. to blame; happened                 B. to blame; was happened  

C. to be blamed; was happened     D. to be blamed ; happened

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So much of interest ________ that most visitors simply run out of time before seeing it all.

A. offers Beijing    B. Beijing offers     C. does Beijing offer     D. Beijing does offer

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We all know that, ________ , the situation will get worse.  

A. not if dealt carefully with       B. if not carefully dealt with     

C. if dealt not carefully with       D. not if carefully dealt with

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 Last year a terrible earthquake happened in the Sichuan Province, __________ the people are still suffering..

A. from their effects        B. of which effects     

C. of its effects              D. from whose effects

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On each side of the street _______a lot of trees.

A. stands        B. stand    C. is standing       D. are grown

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          around the Water Cube, we were then taken to see the Bird’s Nest for the 2008 Olympic Games.

A. Having shown    B. To be shown    C. Having been shown    D. To show

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He went out without an umbrella,________ in the rain.

A. risked being caught        B. risking being caught

C. risked to be caught         D. risking to be caught

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科目: 来源: 题型:

---- Thank you for your help.

---- ____________.

A. I’m glad to   B .All right    C. Any time    D. So long

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