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问题 单项选择题

抗“O”试验测定的是（）

A.A族溶血性链球菌的代谢产物

B.A族溶血性链球菌的溶血毒素

C.抗A族溶血性链球菌溶血素“O”的抗体

D.溶血毒素的溶细胞毒性

E.O型链球菌抗体

答案

参考答案：C

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完形填空

     Jimmy is very   1   at Maths.
     Mary, his sister, doesn't do well   2   it. Jimmy often helps her with her Maths. One night Jimmy
and Mary took out their exercise-books and began   3   their lessons. Soon Jimmy finished   4   his
homework, but his sister   5  . She couldn't work   6   the last(问题). "Let me   7   you," said Jimmy.
"No, please   8  . I'll do it myself, " said Mary. She thought hard, an hour   9  , she worked it out. She
was very tired, but very, very   10  .

( )1. A. good    
( )2. A. at      
( )3. A. to make  
( )4. A. do      
( )5. A. couldn't
( )6. A. on      
( )7. A. to help  
( )8. A. didn't  
( )9. A. after    
( )10.A. sorry		B. better      
B. in          
B. do          
B. to do      
B. don't    
B. out        
B. to speak    
B. couldn't  
B. later      
B. bad		C. fine      
C. on        
C. to do    
C. did       
C. needn't
C. at        
C. help      
C. can't  
C. behind    
C. happy		D. well    
D. of      
D. of      
D. doing    
D. can't
D. for      
D. to tell  
D. don't
D. in      
D. angry
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选择题

地球自转产生了（  ）

A．昼夜现象

B．昼夜交替现象

C．极昼极夜现象

D．太阳直射点的季节移动
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