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问题 选择题

下列实验相关现象的描述正确的是（　　）

A．磷在氧气中燃烧产生大量白色烟雾

B．铁丝在氧气中燃烧，火星四射，生成黑色

C．硫在空气中燃烧，发出明亮的蓝紫色火焰

D．蜡烛在氧气中燃烧生成二氧化碳和水

答案

现象描述不说是什么而说什么样．

A、磷在氧气中燃烧的现象是：发出白光，放出大量的热，产生大量的白烟，不是白白色烟雾，所以错误．

B、铁丝在氧气中燃烧的现象是：剧烈燃烧，火星四射，放出大量的热，生成一种黑色固体，所以正确．

C、硫在空气中燃烧的现象是：发出淡蓝色的火焰，放出大量的热，生成一种有刺激性气味的气体，火焰颜色不对，所以错误．

D、蜡烛在氧气中燃烧生成二氧化碳和水，这不是描述实验现象，只是说明反应产物，所以错误．

故选B．

完形填空
完形填空。

     Years ago in Scotland, the Clark family had a dream. Clark and his wife worked and   1   , making
plans for their nine children and themselves to travel to    2  . It had taken years, and they had   3    saved
enough money and had got passports (护照) and    4   for the whole family to the United States.
     The entire family was filled with   5   about their new life.    6   , seven days before their departure, the
youngest son was bitten by a dog. The doctor sewed up the boy but he   7   a yellow sheet on the
Clarks' front door.   8   the possibility of rabies (狂犬病), they should be quarantined (隔离) for
fourteen days.
     The family's   9   was destroyed. They would not be able to make the trip to America as they had 
  10  . The father, filled with disappointment and   11   , hurried to the dock to watch the ship leave-without
the Clark family.   12   of disappointment came to the father. Five days    13   , the tragic news spread
throughout Scotland - the mighty Titanic had sunk. The unsinkable ship had sunk,   14   many lives with
it. The Clark family should have been on that ship,   15   because the son had been bitten by the dog,
they were   16   in Scotland. When Mr. Clark heard the news, he    17  his son and thanked him for saving
the family. He thanked God for saving their lives and turning   18   he had felt was a(n)   19   into a
blessing.
     Although we may not always understand, all things    20   for a reason.

( ) 1. A. spent    
( ) 2. A. America  
( ) 3. A. instantly
( ) 4. A. cars    
( ) 5. A. creativity
( ) 6. A. However  
( ) 7. A. signed  
( ) 8. A. Apart from
( ) 9. A. passport
( )10. A. imagined  
( )11. A. tension  
( )12. A. Information
( )13. A. later    
( )14. A. saving  
( )15. A. so      
( )16. A. left behind
( )17. A. envied  
( )18. A. when    
( )19. A. sacrifice
( )20. A. remain  		B. counted    
B. Europe    
B. obviously  
B. ships      
B. excitement
B. Besides    
B. brought    
B. In spite of
B. ship      
B. planned    
B. courage    
B. Tears     
B. after      
B. leaving    
B. or        
B. given out  
B. called    
B. what      
B. experience  
B. disappear  		C. saved    
C. Japan    
C. originally
C. tickets  
C. surprise  
C. Instead  
C. hung      
C. As for  
C. house    
C. admitted  
C. anger    
C. Letters  
C. late      
C. taking    
C. and      
C. turned away
C. blamed    
C. that      
C. comedy    
C. happen     		D. played    
D. Africa    
D. finally    
D. rooms      
D. imagination
D. Otherwise  
D. raised    
D. Because of
D. dream      
D. claimed    
D. doubt      
D. News      
D. over      
D. killing    
D. but        
D. taken over
D. hugged    
D. why        
D. misery    
D. exist      
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单项选择题

气压制动器的驱动力完全由（）产生。

A、液压

B、气压

C、脚踏板

D、制动蹄
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