【单选题】
如果上一级保护失控，加热管继续加热，加热腔将被烧干，当电热管露出水面时，加热腔内的温度进一步提高、达到规定温度值时，装在___上的温度保险器动作，切断加热回路，确保安全。
A. 冷水缺水保护器
B. 开水满水保护器
C. 磁化过滤器
D. 加热管
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答案
D
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【单选题】
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【单选题】
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【单选题】
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【单选题】
25. _______ are you going to the School Uniform Exhibition, Amy ?
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( ) 26. Where does the writer of "The little Prince" come from?
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A. A
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【单选题】
( ) 27. What does the prince do after the fox tells him a secret?
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D．He discovers interesting things such as a snake, other roses and a fox
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( ) 28. What does "The little Prince" mainly talk about? It' s about _________．
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【单选题】
( ) 29. What is the writer's main purpose（目的）in writing this passage？
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B．To tell people what kind of person his father was．
C．To tell the readers what present he got from his father．
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A. A
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C. C
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【单选题】
( ) 30. Why did the father not ask his son not to do this and do that？
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C．Because he was a man of few words．
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【单选题】
( ) 32. What may be the proper Chinese for the underlined part in the passage？
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A. A
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【单选题】
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【单选题】
( ) 34. Judy Foreman copied down the phrase because she ___ .
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【单选题】
( ) 35. Who came up with the phrase according to the passage?
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A. A
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【单选题】
( ) 36. What can we infer from the last paragraph?
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C. People should practice random kindness to strangers they meet.
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A. A
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C. C
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【单选题】
( ) 37.The greatest river for navigation is ___________.
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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
C. irrigation and making electricity D. washing clothes
A. A
B. B
C. C
D. D
【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
C. chemicals and other materials D. people's building a dam across a river
A. A
B. B
C. C
D. D
【单选题】
( ) 40. The best title of the passage is ___________.
A. Rivers in Cities B. The importance of Rivers
C. Transportation D. Natural Resources
A. A
B. B
C. C
D. D
