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问题 单项选择题

下列推理正确的是：

A．只有开启电源开关，电脑才会运行；这台电脑没运行，可见没有开启电源开关

B．翻译要学好外语，我又不当翻译，所以，我无须学好外语

C．如果公路被冰雪覆盖，汽车就不会按时回来。果然汽车没有按时回来，可见，公路被冰雪覆盖了

D．鸵鸟不会飞，鸵鸟是鸟，所以，有的鸟不会飞

答案

参考答案：D

解析： D项符合三段论，正确。B项不符合三段论推理。充分条件假言推理，比如，“如果……就”，其假言推理规则：(1)肯定前件式：有前件就有后件；(2)否定后件式：没有后件就没有前件。C项错误。必要条件假言推理，比如“只有……才”，其假言推理规则：(1)肯定后件式：有后件就有前件；(2)否定前件式：没有前件就没有后件。故A项推理错误。

完形填空
完形填空。
     My husband Jeff and I moved into our new home in Scottsbluff last year just before Christmas. I did not
have the   1   or energy to carry out my traditional Christmas decorating and baking activities. What was the
point, anyway? It was going to be a   2   Christmas after all. 
       3  , the neighborly nature of west Nebraska residents started to trickle (陆续来临) in.
     There was a   4   on the door one evening. It was Jeff's new colleague, John Smith, and his wife, Phyllis.
The Smiths had stopped by to   5   us to town with a loaf of homemade bread. They pointed out a   6   on the
porch (门廊). Apparently the doorbell wasn't working in the cold snowy weather and we had   7   a visit from
the Browns, our across-the-street neighbors, who brought us a Christmas card and more Christmas cookies.
     The   8   feelings brought by these thoughtful gestures lasted longer than the food.
     As Jeff and I were clearing pre-Christmas   9   from our driveway, Ernie Guzman came over from next door
to  10  us to dig out.
     Then, we received an invitation to  11  a Christmas Eve meal with our neighbors, Ernie and Nancy Sommer,
and their  12  -a 90-year-old lady, who also had no family in the immediate area with whom to spend the holiday.
Our Christmas Eve was quite merry, thanks to our  13 .
     Our Christmas morning  14  was special, thanks to the Smiths' gift of bread. I was so  15  for these gestures
of welcome, especially during the holidays.
     This year, we were again unable to be with our families for Christmas. The  16  and work schedules just
made things too difficult.  17  that sense of Christmas isolation (孤立) all too well, we decided to try to round
up some other folks who were  18  in the holidays.
     Lonely people are all around us, but most of us  19  notice them. Just take a look around you. Sometimes,
the smallest  20  gesture can make a world of difference.
( )1. A. chance  
( )2. A. merry   
( )3. A. Therefore
( )4. A. card    
( )5. A. welcome 
( )6. A. tree    
( )7. A. forgot  
( )8. A. deep    
( )9. A. snow    
( )10. A. teach  
( )11. A. share  
( )12. A. aunt   
( )13. A. folks  
( )14. A. call   
( )15. A. sorry  
( )16. A. distance
( )17. A. Studying
( )18. A. alone  
( )19. A. always 
( )20. A. careful 		B. time         
B. free         
B. Meanwhile    
B. sign         
B. invite        
B. package       
B. arranged    
B. true         
B. rubbish        
B. help         
B. prepare      
B. guest         
B. relatives   
B. greeting     
B. eager         
B. expense     
B. Showing      
B. busy         
B. seldom        
B. patient  

C. anxiety        
C. lonely      
C. Somehow      
C. knock        
C. drive        
C. mail           
C. received     
C. warm        
C. dust           
C. urge          
C. taste        
C. maid           
C. colleagues 
C. breakfast    
C. ready        
C. season       
C. Knowing     
C. happy          
C. finally        
C. vague     

D. ability           
D. usual         
D. However          
D. note             
D. send            
D. flower              
D. missed       
D. mixed           
D. leaves          
D. forbid             
D. exchange       
D. partner            
D. neighbors    
D. meeting         
D. grateful        
D. situation     
D. Discovering                
D. active            
D. usually         
D. kind        

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问答题

Going to the ballpark, visiting friends and playing bingo are simple diversions for many of us. But for the elderly, these social pastimes may play a critical role in preserving their physical and mental health.

(46) In fact, a new study suggests that the less time older people spend engaged in social activity, the faster their motor function tends to decline. "Everybody in their 60s, 70s and 80s is walking more slowly than they did when they were 25," says Dr. Aron Buchman, a neurologist at the Rush University Medical Center in Chicago and leading author of the study, which was published in the June 22nd issue of the Archives of Internal Medicine. (47) "Our study shows the connection between social activity and motor function--and opens up a whole new universe of how we might intervene. "

(48) An increasing body of evidence has suggested that participating in mentally stimulating activity, socializing frequently and exercising may help protect against age-related decline-at least cognitive decline. As early as 1995, neuroscientist Carl Cotman, who studies aging and dementia at the University of California at Irvine, published a paper in Nature showing that physical exercise produces a protein that helps keep neurons from dying and spurs the formation of new neural connections in the brain. (49) More recently, Cotman demonstrated in studies of elderly dogs and mice that enriching their social environment is associated with improvement in brain function.

Researchers are also finding that social activity may be linked to the same protective effect in people. A recent study of 2 500 adults ages 70 to 79, published in the journal Neurology, found that those who were able to stay mentally sharp were also those who exercised once a week or more, had at least a ninth grade literacy level and were socially active.

While further research needs to be done to establish the exact impact of social activity and exercise on specific age-related declines (50) it’s likely that a reduction in social activity may simply be a symptom of physical decline, since people may naturally withdraw from social engagement as they lose motor skills-most researchers would agree that it is not unreasonable to encourage seniors to get out there more. Only 10% of people over 65 get the recommended amount of exercise (at least 2. 5 to 5 hours a week), and given that seniors already tend to be more socially isolated than younger adults, it’s difficult to motivate them to become more active. "If you are alone, you are less likely to follow recommendations," notes Verghese. It might help, though, if you visit Grandma more often and let her know that a regular pastime may just help her stay fitter and sharper longer.

(48) An increasing body of evidence has suggested that participating in mentally stimulating activity, socializing frequently and exercising may help protect against age-related decline-at least cognitive decline.
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