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问题 选择题
下列叙述正确的有（　　）
A．紫外线照射某金属表面时发生了光电效应，则红外线也一定可以使该金属发生光电效应
B．光电效应证实了光具有粒子性
C．汤姆逊在α粒子散射实验的基础上，提出了原子的核式结构模式
D.++X，符号“X”表示中子
答案

答案：B

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     Many people around the world study English.  English is spoken in more
than forty _1   all over the world.  It is the only    2    that is spoken in so
many countries.  If you learn English well, it will be much easier for you
to   3   with people in English-speaking countries. It is not easy to learn
English,_4 you need to work hard. Where there is a will, there is a   5   . You can watch English   6    programs,English films on DVD or videos. You can   7   with your classmates in and out of class. You can speak to foreign
friends   8   the phone in English. You can also read English books,
newspapers and magazines and _ 9    letters or e-mails to your friends in
English.  If you study hard, you are    10    to make progress.
( )1. A. countries  
( )2. A. sport      
( )3. A. communicate
( )4. A.but        
( )5. A.road        
( )6. A.tape        
( )7. A.ask        
( )8. A.in          
( )9. A.write      
( )10.A.tired       		B. cities  
B. language
B. compete  
B.because  
B.street    
B.TV        
B.reply    
B.for      
B.send      
B.kind      		C. schools
C. culture
C. fight  
C.so      
C.path    
C.MP3      
C.talk    
C.to      
C.post    
C.sure     		D. villages    
D. art        
D. travel      
D.then        
D.way          
D.computer    
D.listen      
D.on          
D.give        
D.ready        
     
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单项选择题

葡萄胎重要的病理特征是()

A．滋养细胞增生

B．绒毛构型完好

C．黄素化囊肿

D．绒毛间质水肿

E．间质内胚源性血管消失
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