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      After almost 30 years of arguing that a black hole swallows up everything that falls into it, British
astrophysicist (天体物理学家) Stephen Hawking moved backward last week.
      The world-famous writer of "Brief History of Time" said he and other scientists had got it wrong.  
     "I've been thinking about this problem for the last 30 years, and I think I now have the answer to it,"
said Hawking. "A black hole only appears to form but later opens up and set free information about
what fell inside. So we can be sure of the past and can predict the future."
      The findings could help solve the "black hole information paradox(似是而非的观点)", an important
puzzle in modern physics.
      A black hole is an area in space where matter is under such pressure that even light can not escape
from its gravitational pull(引力). But, exactly what happens there has long puzzled scientists.
      Black holes occur when a powerful star burns up its nuclear fuel and gravity forces it to break down
in on itself. The great weight of the star's outer layers moves in towards its center. The force of gravity
keeps nearly all light from escaping and nothing inside can be seen from the outside.
      The star actually disappears from the universe into a point of infinite density(高密度). That is a place
where the laws of general relativity that govern space and time break down.
     Hawking has devoted most of his life to studying these questions.
     At the beginning, cosmologists believed the holes were like a "universal vacuum (真空) cleaner",
sucking up everything in their path.
      Hawking revolutionized the study of black holes when he proved, in 1976 that, under the strange
rules of quantum physics(量子物理), when black holes form they send out energy and lose mass in the
process.
      In thinking up this so-called "Hawking radiation", the Cambridge mathematician also created one of
the biggest puzzles in physics.
      These particles (粒子), he said, contained no information about what has been occurring inside the
black hole, or how it formed. Under his theory, once the black hole disappears, all the information within
it is lost.
1. What's the importance of Hawking's new findings?    
A. They could help solve the puzzle about black holes.
B. They has solved the mystery of "black holes".
C. We can now know what is going on inside "black holes".
D. Scientists have already predicted the future of "black holes" now.
2. What's the meaning of the underlined word "cosmologist" (in Paragraph 9)?  
A. A person who studies the universe and its origin and development. 
B. A person who studies the stars and their development.
C. A person who travels in a spacecraft.
D. A person who studies the position of the stars and the movements of the planets.
3. Which of the following is TRUE?  
A. Hawking has now studied black holes for more than 40 years.
B. During the course of the black hole's forming the enormous weight of the star's center
moves into the outer layers.
C. Almost nothing can escape from the gravitational pull of the black hole.
D. Scientists have been thinking the black hole contains no information.
4. What would be the best title for the passage?  
A. The Formation of the Black Hole 
B. Black Hole Information Paradox
C. Black Hole Mystery
D. The Cause of the Black Hole
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科目:高中英语 来源:同步题 题型:完形填空

完形填空。
     When I come across a good article in reading newspapers. I often want to cut and keep it. But just as I am about to do so I find the article on the   1   side is as much interesting. It may be a discussion of the
way to   2   in good health, or a   3   about how to behave and conduct oneself in society. If I cut the front article, the opposite one is likely to   4   damage, leaving out half of it or keeping the text   5   the title.
Therefore, the scissors would   6   before they start,   7   halfway done when I find out the   8   result.
     Sometimes two things are to be done at the same time, both worth you   9  .You can only take up one of them, the other has to wait or be   10   up. But you know the future is unpredictable (不可预料) - the
changed situation may not allow you to do what is left   11  . Thus you are   12   in a difficult position and
feel sad. How   13   that nice chances and brilliant ideas should gather around all at once? It may happen
that your life   14   greatly on you preference of one choice to the other.
     In fact that is what   15   is like, we are often   16  with the two opposite sides of a thing which are both desirable like a newspaper cutting. It often occurs that our attention is drawn to one thing only   17   we get into another. The   18  may be more important than the latter and give rise to a divided mind. I   19 
remember a philosopher's remarks, "When one door shuts, another opens in life." So a casual (不经意) 
  20   may not be a bad one.
(     )1. A. front    
(     )2. A. get      
(     )3. A. advice    
(     )4. A. suffer    
(     )5. A. on        
(     )6. A. use      
(     )7. A. or        
(     )8. A. satisfying
(     )9. A. courage  
(     )10. A. given    
(     )11. A. near    
(     )12. A. filled  
(     )13. A. dares    
(     )14. A. improves
(     )15. A. study    
(     )16. A. faced    
(     )17. A. before  
(     )18. A. following
(     )19. A. still    
(     )20. A. treatment
B. same  
B. keep  
B. news  
B. reduce
B. for    
B. handle
B. but    
B. regretful
B. strength
B. held  
B. alone  
B. attracted
B. comes  
B. changes
B. society
B. supplied
B. after  
B. next  
B. also  
B. action
C. either    
C. lead      
C. theory    
C. prevent  
C. without  
C. prepare  
C. so        
C. surprising
C. attention
C. made      
C. about    
C. caught    
C. deals    
C. progresses
C. nature    
C. connected
C. until    
C. above    
C. once      
C. choice    
D. opposite  
D. bring    
D. report    
D. cause    
D. off      
D. stay      
D. for      
D. impossible
D. patience  
D. picked    
D. behind    
D. struck    
D. does      
D. goes      
D. life      
D. fixed    
D. as        
D. former    
D. almo st  
D. remark    

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