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问题 问答题

[说明]

设有三个关系

学生S(学号，姓名，性别，年龄，籍贯)

课程C(课程号，课程名，任课老师，所用教材)

学生成绩SC(学号，课程号，得分)

其中规定各属性定义如下：

学号：SNUM 姓名：SNAME 性别：SEX 年龄：AGE 籍贯：NATIVE

课程号：CNUM 课程名：CNAME 任课老师：TEACHER 所用教材：BOOK

得分：GRADE

试用关系代数表达式表示下列查询语句。

[问题2]
检索选修全部课程的学生的学号和姓名。

答案

参考答案：

ПSNUM,CNUM(SC)÷ПCNUM(C)

ПSNUMM,SNAME(S)

完形填空
完形填空。

     Years ago in Scotland, the Clark family had a dream. Clark and his wife worked and   1   , making
plans for their nine children and themselves to travel to    2  . It had taken years, and they had   3    saved
enough money and had got passports (护照) and    4   for the whole family to the United States.
     The entire family was filled with   5   about their new life.    6   , seven days before their departure, the
youngest son was bitten by a dog. The doctor sewed up the boy but he   7   a yellow sheet on the
Clarks' front door.   8   the possibility of rabies (狂犬病), they should be quarantined (隔离) for
fourteen days.
     The family's   9   was destroyed. They would not be able to make the trip to America as they had 
  10  . The father, filled with disappointment and   11   , hurried to the dock to watch the ship leave-without
the Clark family.   12   of disappointment came to the father. Five days    13   , the tragic news spread
throughout Scotland - the mighty Titanic had sunk. The unsinkable ship had sunk,   14   many lives with
it. The Clark family should have been on that ship,   15   because the son had been bitten by the dog,
they were   16   in Scotland. When Mr. Clark heard the news, he    17  his son and thanked him for saving
the family. He thanked God for saving their lives and turning   18   he had felt was a(n)   19   into a
blessing.
     Although we may not always understand, all things    20   for a reason.

( ) 1. A. spent    
( ) 2. A. America  
( ) 3. A. instantly
( ) 4. A. cars    
( ) 5. A. creativity
( ) 6. A. However  
( ) 7. A. signed  
( ) 8. A. Apart from
( ) 9. A. passport
( )10. A. imagined  
( )11. A. tension  
( )12. A. Information
( )13. A. later    
( )14. A. saving  
( )15. A. so      
( )16. A. left behind
( )17. A. envied  
( )18. A. when    
( )19. A. sacrifice
( )20. A. remain  		B. counted    
B. Europe    
B. obviously  
B. ships      
B. excitement
B. Besides    
B. brought    
B. In spite of
B. ship      
B. planned    
B. courage    
B. Tears     
B. after      
B. leaving    
B. or        
B. given out  
B. called    
B. what      
B. experience  
B. disappear  		C. saved    
C. Japan    
C. originally
C. tickets  
C. surprise  
C. Instead  
C. hung      
C. As for  
C. house    
C. admitted  
C. anger    
C. Letters  
C. late      
C. taking    
C. and      
C. turned away
C. blamed    
C. that      
C. comedy    
C. happen     		D. played    
D. Africa    
D. finally    
D. rooms      
D. imagination
D. Otherwise  
D. raised    
D. Because of
D. dream      
D. claimed    
D. doubt      
D. News      
D. over      
D. killing    
D. but        
D. taken over
D. hugged    
D. why        
D. misery    
D. exist      
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单项选择题 A1/A2型题

全口覆盖义齿基牙的选择通常多选择（）

A.第一磨牙

B.第二磨牙

C.尖牙

D.第一前磨牙

E.侧切牙
查看答案