问题 填空题

钨极氩弧焊时,电弧过短,则钨极易与焊丝或熔池相碰,造成焊缝表面污染和()缺陷,并破坏电弧的稳定燃烧。

答案

参考答案:夹钨

完形填空
完形填空.

    All over the world people swim for fun. Swimming is enjoyed by people of 1 ages, from the very
young to the very old. There are many places for people to swim in swimming pools. Many schools,
hotels and clubs have swimming pools. Some people have pools of 2 in their yards.
    Swimming is one of 3 forms of exercise. It can 4 hearts and bodies strong. It can also help blood
circulate(循环). Handicapped(残疾的)people can keep their bodies in better condition by swimming 5
they can't enjoy sports.
    6 is a good idea for parents to see to it(务必做到) that their children learn to swim 7 an early age.
So their children will 8 it for the rest of their lives.
    There are many rules for water safety. These rules can help save not only your life 9 the life of a friend. 
 First of all, know 10 . Many schools 11 wimming lessons to children. Adults(成人) can learn to swim at
public pools. 12 rule to remember is never to swim 13. Always swim with a friend and know 14  in the
water at all times. It is best to swim 15in safe places if you are beginners. If every one learned to swim
and obeyed the rules for water safety, most drawing(溺水) could be avoided.  

(   )1.A.all            
(   )2.A.them            
(   )3.A.good            
(   )4.A.help            
(   )5.A.though          
(   )6.A.That            
(   )7.A.over            
(   )8.A.learn          
(   )9.A.and aim        
(   )0.A.how to swim    
(   )11.A.have          
(   )12.A.The other one  
(   )13.A.alone          
(   )14.A. what person is
(   )15.A.nearly        
B. any                
B.their own            
B. better            
B. let                
B. as                
B. There              
B. during            
B. enjoy              
B. still              
B. why swimming        
B. take              
B. Other              
B. yourself          
B. where that person is
B. hardly            
C. some            
C. theirs own        
C. best            
C. make            
C. so              
C. This            
C. at              
C. stop            
C.and yet          
C. how swimming      
C. give            
C. Others            
C. lonely          
C. who is that person
C. almost            
D. both              
D. their own's        
D. the best          
D. show              
D. until              
D. It                
D. on                
D.know                
D. but also          
D. why to swim        
D. make              
D. Another            
D. together          
D. where is that person
D. only                

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