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问题 选择题

分子式C4H8O2的有机物与硫酸溶液共热可得有机物A和B。将A氧化最终可得C，且B和C为同系物。若B可发生斐林反应，则原有机物的结构简式为

A．HCOOCH2CH2CH3            B．CH3COOCH2CH3

C．CH3CH2COOCH3              D．HOCH2CH2CH2CHO

答案

答案：A

由题意可知C4H8O2为酯，在硫酸溶液共热可水解成醇、羧酸，又A氧化最终可得C，即A为醇、B为羧酸；B和C为同系物即C为羧酸；又B可发生斐林反应，所以可得B这种羧酸为HCOOH，即C4H8O2为酯为甲酸某酯，符合的只有A选项为甲酸丙酯；

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   The purpose of a letter of application(求职信) is to help you to "sell" yourself. It should state__1_
the    job you want, and should tell what your abilities are and what you have__2_. It should be simple,
human,  personal and brief without _ 3 _ out any necessary facts.
   In writing a letter of application, keep in __4__ that the things a possible employer is most _5__ to
want to know about are your qualifications(条件), your achievements and your aims. The opening
paragraph is perhaps the most important part. _6__ the first few sentences fail to _7__ the reader's
attention, the rest of the letter may not be __8_ at all. Try to key your opening remarks to the needs
or interests of the employer not __9_ your own need or desires. For example, instead of beginning
with "I saw your _ 10_ in today's newspaper," you might say "I have made a careful _11_ of your
advertising during the past six months" or "I have made a survey in my neighborhood to find out how
many housewives _12_ your product and why  they  like it. "
   Try to _13_ generalities. Be clear about the kind of job for which you are now _14_. College
graduates  looking for their first positions often ask "What can I _15_  in a letter? Employers want
experience-which, naturally, no ___16___ has." The answer is that everything you have ever done
is _17_.
   It is important to write a good strong closing for your letter. _18__ a specific request for an interview
or give the possible employer something definite to do or expect. An excellent  _ 19_ is to enclose
(内附) a stamped, self-addressed envelope with your letter. That makes it _ 20_ for a possible employer
to get in  touch with you.

( )1. A. clearly      
( )2. A. found        
( )3. A. sending      
( )4. A. brain        
( )5. A. probable      
( )6. A. While         
( )7. A. pay          
( )8. A. kept          
( )9. A. to            
( )10. A. advertisement  
( )11. A. watch        
( )12. A. change      
( )13. A. avoid        
( )14. A. losing      
( )15. A. offer        
( )16. A. worker      
( )17. A. success      
( )18. A. Make        
( )19. A. result      
( )20. A. happier       		B. carefully  
B. done      
B. taking    
B. sight      
B. possible  
B. Although  
B. win        
B. continued  
B. for        
B. report    
B. search    
B. make      
B. remember  
B. applying  
B. supply    
B. beginner  
B. development  
B. Ask        
B. decision  
B. easier     		C. obviously
C. known    
C. leaving  
C. order    
C. likely  
C. As      
C. show    
C. written  
C. into    
C. article  
C. study    
C. sell    
C. protect  
C. preparing
C. mean    
C. owner    
C. practice
C. State    
C. promise  
C. cheaper  		D. easily      
D. heard        
D. picking      
D. mind        
D. able        
D. If          
D. fix          
D. read        
D. from        
D. introduction
D. discussion  
D. use          
D. gain        
D. fitting      
D. provide      
D. manager      
D. experience.  
D. Get          
D. idea        
D. safer        
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单项选择题 A2型题

患者右下肢无力3个月，左下半身麻木，检查左 * * 水平以下痛温觉减退，右膝腱反射亢进，右Babinski（+），右髂前上棘以下音叉振动觉减退，右足趾位置觉减退，病变为（）。

A．胸髓3水平横贯性损害 

B．右侧胸髓3水平半侧损害 

C．左侧胸髓3水平半侧损害 

D．右侧胸髓3水平后索损害 

E．左侧胸髓3水平后索损害
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