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问题 单项选择题

下面关于PC机输入/输出接口的叙述中，正确的是：

A．USB1.1的运行速度比USB2.0快

B．当PC机具有COM1及COM2两个串口时，采用RS 232标准的外设既可与COM1相连，也可与COM2相连

C．IDE接口和EPP接口均以并行方式传送信息，因此采用IDE接口的外设既可与EPP接口相连，也可与IDE接口相连

D．RS 232接口和USB均以串行方式传送信息，因此它们的连接器具有相同的物理尺寸和外形

答案

参考答案：B

解析：USB2.0是USB1.1规范向后兼容的扩展，它比最初的1.0和1.1版运行快40 倍，所以A的说法是错的。根据RS-232C标准规定连接电缆和机械、电气特性、信 号功能及传送过程。目前在IBM PC机上的COM1、COM2接口，就是RS-232C接 口，选项B正确：接口标准不同，所用的连接器以及接口外观尺寸是不同的，不可， 以将不同标准的接口彼此连接，选项C和D错误。

完形填空
完型填空。
     Our dog named Zip always brings things home for us to keep! Many of
them were toy bears, lambs and ducks. We never could     1     the owners.
     One day Dad was     2     the newspaper, "Listen to this, everybody," he
said. "To the person who took a Teddy bear from a child's wagon(推车)
please bring back the toy bear. Our two-year-old son is very     3     ."
     "Zip does something     4     again. He must have taken others' toys." said
Anita.
     "Yes," said Dad, "Well, the paper gives the     5     . This time I can take
back Zip's     6    ."
     "Do you think it is    7     to do that?" Mom asked. "If you tell others about Zip, who will believe you?"
     "I will     8     until dark. Then I'll just put the Teddy bear at the front door and walk away.    9 will see me."
     Dad's idea     10     worked. He put Teddy at the gate. He turned to walk
away and knocked into a chair!
     Dad started to     11     . But he didn't get very far. The gate light came on. A man opened the door."    12     is over here?" he called out.
     Dad kept silent and didn't even try to     13     . He just wanted to get away. Then the man saw     14    .
     He shouted after Dad, "How    15     you are!" he said, "Taking toys from
babies!"
( ) 1.A. pay  
( ) 2.A. buying
( ) 3.A. sad  
( ) 4.A. wrong
( ) 5.A. picture
( ) 6.A. food  
( ) 7.A. wrong
( ) 8.A. speak
( ) 9.A. Someone
( ) 10.A. never
( ) 11.A. speak
( ) 12.A. What
( ) 13.A. help  
( ) 14.A. the bear
( ) 15.A. angry 		B. agree  
B. reading
B. surprised
B. important
B. story  
B. name    
B. clever  
B. wait    
B. Everyone
B. always  
B. drive  
B. Who     
B. answer  
B. Zip     
B. kind    		C. find        
C. writing    
C. happy      
C. interesting
C. address    
C. idea        
C. dangerous  
C. watch      
C. No one      
C. already    
C. run        
C. How         
C. listen      
C. nothing    
C. bad        		D. choose      
D. sending    
D. afraid      
D. worried    
D. time        
D. present    
D. free        
D. think      
D. Anyone      
D. almost      
D. cry        
D. Which      
D. knock      
D. the baby    
D. sorry      


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单项选择题

世界电信日为每年的（）

A.5月15日

B.5月17日

C.5月18日

D.5月19日
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