【单选题】
二氧化碳气体保护焊时,为了控制熔深,一般调节___
A. 燃弧时间
B. 电流大小
C. 焊丝粗细
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答案
B
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相关试题
【单选题】
下列关于电子束真空室的说法错误的是___
A. 真空室的尺寸及形状应根据焊剂的用途和被加工的零件来确定
B. 真空室一般采用低碳钢和不锈钢制成，碳钢制成的工作时内表面应镀镍
C. 电子束焊剂的使用者可自行改装真空室
【单选题】
关于气力引射器下列说法正确的是___
A. 气力引射器适用于焊接大而长的焊件时排除电焊烟尘科有毒气体
B. 气力引射器对焊接区实行密闭,能最大限度地减少臭氧等有毒气体的弥散
C. 气力引射器的原理是利用压缩空气从主管中高速喷出时,在副管形成负压区,从而将电焊烟尘和有毒气体吸出
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【单选题】
( ) 27. What does the prince do after the fox tells him a secret?
A．He cares more about a flower and a sheep．
B．He meets many more strange adults on other planets．
C．He realizes his love for the rose and he goes back to his planet．
D．He discovers interesting things such as a snake, other roses and a fox
A. A
B. B
C. C
D. D
【单选题】
( ) 28. What does "The little Prince" mainly talk about? It' s about _________．
A．the adult world B．the planet B -612
C．a rose and a fox D．the adventure of a young prince
A. A
B. B
C. C
D. D
【单选题】
( ) 29. What is the writer's main purpose（目的）in writing this passage？
A．To tell the readers his life story．
B．To tell people what kind of person his father was．
C．To tell the readers what present he got from his father．
D． To let people know how poor he was．
A. A
B. B
C. C
D. D
【单选题】
( ) 30. Why did the father not ask his son not to do this and do that？
A．Because he felt quite confident of his son．
B．Because he was born from a poor family．
C．Because he was a man of few words．
D．Because he didn't want to be much too strict with his son．
A. A
B. B
C. C
D. D
【单选题】
( ) 31. What would someone learn from this passage？
A．How to live by oneself． B．How to stand on one's own feet．
C．What a good father should do． D．What the self-important is like．
A. A
B. B
C. C
D. D
【单选题】
( ) 32. What may be the proper Chinese for the underlined part in the passage？
A．闲暇时光 B．学费 C．精神空虚 D．经济不足
A. A
B. B
C. C
D. D
【单选题】
( ) 33. Why did Natalie Smith pay for the six cars behind her?
A. She had seven tickets.
B. She hoped to please others.
C. She knew the car drivers well.
D. She wanted to show kindness.
A. A
B. B
C. C
D. D
【单选题】
( ) 34. Judy Foreman copied down the phrase because she ___ .
A. thought it was beautifully written
B. wanted to know what it really meant
C. decided to write it on a warehouse wall
D. wanted her husband to put it up in the classroom
A. A
B. B
C. C
D. D
【单选题】
( ) 35. Who came up with the phrase according to the passage?
A. Judy Foreman. B. Natalie Smith. C. Anne Herbert D. Alice Johnson.
A. A
B. B
C. C
D. S
【单选题】
( ) 36. What can we infer from the last paragraph?
A. People should practice random kindness to those in need.
B. People who receive kindness are likely to offer it to others.
C. People should practice random kindness to strangers they meet.
D. People who receive kindness are likely to pay it back to the giver.
A. A
B. B
C. C
D. D
【单选题】
( ) 37.The greatest river for navigation is ___________.
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A. A
B. B
C. C
D. D
【单选题】
( ) 38. From a dam, people can use the water for ___________.
A. keeping the rivers clean B. only making electricity
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A. A
B. B
C. C
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【单选题】
( ) 39. The water in the river is polluted because of _____________.
A. people's drinking water too much B. people's swimming in the river too much
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【单选题】
( ) 40. The best title of the passage is ___________.
A. Rivers in Cities B. The importance of Rivers
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B. B
C. C
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【单选题】
) 1. Even Tony’s six-year-old son asked him ______ smoking.
A. stops B. stopped C. to stop D. stopping
A. A
B. B
C. C
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【单选题】
2.—What do you think of the lecture of Li Yang’s Crazy English?
— I think it’s _______ , but someone thinks it’s much too ________.
A. wonderful enough; bored B. enough wonderful; boring
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A. A
B. B
C. C
D. D
【单选题】
3.—He didn’t go to the lecture this morning, did he?
— _____ ．Though he was not feeling very well．
A. No, he didnt B. Yes; he did C. No, he did D. Yes, he didnt
A. A
B. B
C. C
D. D
【单选题】
4. If you read a lot, your life ______ full of pleasure.
A. will be B. is C. be D. was
A. A
B. B
C. C
D. D
【单选题】
5. The black bag _________ be Annas. She has a blue one.
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A. A
B. B
C. C
D. D
【单选题】
6. Susan, why are you still here? They are all ready to start.
Im sorry, but I _________ when to start.
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A. A
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【单选题】
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B. B
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【单选题】
8. — Could you tell me ______? I must find him．
— Sorry．I don’t know．But he was here just now．
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【单选题】
9. —What did Mr Green say to you?
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B. B
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【单选题】
10. I often see Tom on the playground．When I passed the playground yesterday, I saw him ．
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【单选题】
11. — Mum, could I have ____________ to drink?
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13. Her son __________ Coke, but now he __________ milk．
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【单选题】
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【单选题】
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【单选题】
17. I often go on holiday with my parents _____ summer.
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A. A
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18. I called you at 4:00 yesterday afternoon, but nobody answered.
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19.––Who is on the playground? ---__________．
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【单选题】
20. The schoolboy ______ a blind man cross the street yesterday.
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21. —The 2010 World Expo which will last 184 days will be held in Shanghai on May 1st.
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22. They preferred ______ in bed rather than _____ horses．
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【单选题】
23. —What was Jim wearing at the party?
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B. B
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【单选题】
24. The 2016 Olympic Games ________ in Brazil. Would you like to go there?
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A. A
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C. C
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【单选题】
25. — David, look at the man in white over there．Can you tell me _______ ?
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【单选题】
( ) 26.With help from a Mr. H, you can__________.
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