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已知蜡烛的主要成分是石蜡．由蜡烛燃烧后生成水和二氧化碳的实验事实，判断石蜡中一定含有哪些元素？

答案

蜡烛燃烧时，由于空气提供了氧元素，且燃烧产物水和二氧化碳中含有碳、氢、氧三种元素，故可推断石蜡中一定含有碳、氢两种元素．

阅读理解
完形填空。
     All over the world people enjoy sports. Sports are   1   people's health. Many people like to watch   2   play
sports games. They buy tickets   3   turn on their TV sets to sit   4   them. Sports   5   with the season. People
play   6   games in different seasons. Sometimes they play inside the room, sometimes they play outside. We
can   7   sports here and there. Some sports are rather interesting.   8   people   9   different countries cannot
understand each other, but after a game they often become very  10   to each other.
(   ) 1. A. good for 
(   ) 2. A. other    
(   ) 3. A. and      
(   ) 4. A. in front 
(   ) 5. A. change   
(   ) 6. A. same     
(   ) 7. A. see      
(   ) 8. A. Sometimes
(   ) 9. A. from     
(   )10. A. friend                          		B. good at       
B. others        
B. but             
B. in the front 
B. are          
 B. different      
B. look           
B. When         
B. to             
B. friendly                      		C. good                  
C. the other           
C. or                         
C. in the front of  
C. play                    
C. the same            
C. find                   
C.  Or                   
C. outside                 
C. friends           		D. good to         
D. the others      
D. so              
D. in front of     
D. start           
D. the different   
D. watch           
D. So              
D. inside          
D. more friendly   
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判断题

第二部分

小王歌唱得非常好。()
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