焊缝金属纵向收缩引起()残余应力。A.横向 B.纵向 C.网状

题型:单项选择题

问题:

焊缝金属纵向收缩引起()残余应力。

A.横向

B.纵向

C.网状

考点:焊工技能考试中级机械焊接工中级机械焊接工题库
题型:单项选择题

阅读理解

       Years ago, a college teacher gave a group of graduate students this job: Go to a poor place. Take

200 boys, between the ages of 12 and 16, and find out their living environment. Then predict their chances for the future.

       After doing some research, the students found that 90% of the boys would spend some linein jail

(监狱).

       Twenty-five years later, another group of students was given the job: Go to test what the first group

of students had predicted. They went back to the same place. These 200 boys lad then become men.

Some of them were still there, a few had died and some had moved away. The students found that only

four of them had ever been sent to jail.

       These men had lived in a place full of crime (犯罪) for many years. Why did they have such a good

record? When the students asked the reason, the men said, "Well, there was a teacher."

       The students found the teacher. What did she do to these boys? Could she give the students any

reason why these boys should have remembered her?

       "No," she said, "no, I really couldn't give any reason." And then, thinking back over the years, she

said happily, "I loved those boys."

1. The first group of the students took ____ boys to help them to do their job.

A. 12            

B. 16            

C. 90            

D. 200

2. The underlined word "predict" in the passage most probably means _____ in Chinese.

A. 证明    

B. 预测    

C. 提供    

D. 证实

3. Which of the following is NOT true?

A. Four of the boys had been sent to jail.  

B. The 200 boys were between 12 and 16.

C. The woman teacher could not give any reason at last.

D. The children lived in a place which was full of crime.

4. What's the main idea of this passage?

A. Predicting never works.  

B. Teacher's love can change children's life.

C. Two hundred boys were tested by students.

D. The two groups of students could predict the boys' future.

题型:单项选择题

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