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问题 选择题

图示为高速摄影机拍摄到的子弹穿透苹果瞬间的照片.该照片经放大后分析出,在曝光时间内,子弹影像前后错开的距离约为子弹长度的1%～2%.已知子弹飞行速度约为500 m/s,由此可估算出这幅照片的曝光时间最接近                                （  ）

A．

B．

C．

D．

答案

答案：B

子弹的长度约为5cm，则曝光时间内子弹移动的距离为，曝光时间

完形填空
完形填空。
     "Sixteen ,"  I said.  I have forgotten the math question my  second-grade teacher, Joyce Cooper asked
that day, but I will never forget my _1_ . As soon as the number left my mouth, the whole class started _2_ . I felt like the silliest person in the world.
     Mrs Cooper fixed them with a firm(严格的) look. Then she said: "We're all here to _3_ ."
     Another time, Mrs Cooper asked us to write a _4_ about what we hoped to do with our lives. I wrote: "I want to be a _5_ like Mrs Cooper."
     She wrote on my report, "You would make an outstanding(杰出的) teacher ___6_ you are determined(坚定的) and you try hard." I was to carry those _7_ in my heart for the next 27 years.
     After I graduated from high school, I got married and had children.
     We needed every penny just to get by. College - and teaching - was out of the question.
     Then one day I thought of my _8_ of how I wanted to help children. I talked it over with my family and _9_ to attend college classes in the mornings before work. And when I got home from work, I would _10_ . Finally after seven years, my dream had been realized and I became a teacher.
     Not long after I started _11_ ,  something  happened that brought the _12_ rushing back to me.  I had
written a sentence with grammatical(语法的) mistakes on the blackboard. Then I asked students to come and _13_ the mistakes.
     One girl got halfway through, became confused(迷乱的) and stopped. As the other children laughed, _14_ rolled down her face.  I gave her a hug and told her to get a drink of water.  Then,  remembering Mrs
Cooper, I fixed _15_ of the class with a firm look. "We're all here to learn," I said.
( )1. A. question
( )2. A. talking
( )3. A. work
( )4. A. letter
( )5. A. teacher
( )6. A. because
( )7. A. reports
( )8. A. plan
( )9. A. supposed
( )10.A. sleep
( )11.A. studying
( )12.A. teacher
( )13.A. correct
( )14.A. water
( )15.A. half 		B. answer
B. shouting
B. learn
B. song
B. friend
B. unless
B. words
B. work
B. promised
B. study
B. writing
B. life
B. prove
B. tears
B. most		C. result
C. discussing
C. play
C. report
C. reporter
C. until
C. teachers
C. dream
C. decided
C. rest
C. thinking
C. past
C. check
C. sweat
C. the whole 		D. reaction      
D. laughing      
D. watch          
D. story          
D. parent        
D. before        
D. classmates    
D. idea          
D. agreed        
D. play          
D. teaching      
D. feeling        
D. read          
D. smiles        
D. the rest      
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填空题

根据句意及首字母提示在横线处填上恰当的单词，使句子意思完整，语法正确。    

1. I'm afraid Lily is too young to take care of h________.   

2. Out teacher is an e_______man.  He doesn't seem to be tired forever.    

3. I'm afraid you can't leave without p_______.    

4. He's very outgoing, so he has a large c_______of friends.    

5. I'm sorry to b_______you.  I didn't know you were asleep.    

6. There are p_______of books in the box.  Each of you can get a different one.    

7. If you have got any problems, you can talk with Lucy.  She's a good l_______.    

8. Sally is a kind girl.  Shc is easy to get along w_______.
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