问题 选择题

现有0、1、2、…、9十个数,

①随机地从这十个数中选取两个数,它们的和为17;

②随机地从这十个数中选取两个数,它们的和为123;

③随机地从这十个数中选取两个数,它们的和为正整数;

④随机地从这十个数中选取两个数,它们的差为-5.

以上事件中,属于确定事件的是(  )

A.①②

B.①③

C.②③

D.②④

答案

①是随机事件,故选项错误;

②是不可能事件,是确定事件;

③是必然事件,是确定事件;

④是随机事件,故选项错误.

故选C.

完形填空
完形填空。
        It was on the afternoon of June 11, 2010. Mr Smith looked at his watch at times. He  1  to go home as soon as possible. There would be a     2   football match in South Africa. This is South Africa's World Cup opening match. He couldn't miss it and he could not do anything in his office. He    3    home after work.
Supper was ready and he went to his     4    after that. But he could not fall asleep. He was afraid he would __5    the match though he had told his wife to wake him up in the night. He had to     6    and began to read some evening newspapers. Finally the match began. His team lost the _    7    half of the match. He became angry. He was so sleepy that he did not know when he had gone to   8   . The next morning his wife brought some bread and milk into the sitting-room. She found he was    9   sleeping on the sofa and called out "Oh, dear! Get up, or you'll be __10   today. It is five to seven!" Hearing this, Mr Smith jumped off the sofa and asked, "Who won?"
( )1. A. hated    
( )2. A. common    
( )3. A. hurried  
( )4. A. classroom
( )5. A. catch    
( )6. A. get up    
( )7. A. last      
( )8. A. work      
( )9. A. ever      
( )10. A. late    
B. hoped    
B. dangerous
B. swam      
B. library  
B. miss      
B. lie down  
B. third    
B. play      
B. yet      
B. early    
C. found      
C. wonderful  
C. walked      
C. shop        
C. lost        
C. stand up    
C. two        
C. sleep      
C. already    
C. ill        
D. liked  
D. lucky  
D. jumped
D. bedroom
D. leave  
D. go away
D. first  
D. rest  
D. still  
D. tired  
单项选择题