【单选题】
下列关于C51中断函数定义格式的描述中，___是不正确的。
A. n是与中断源对应的中断号，取值为0~4
B. m是工作寄存器组的组号，缺省时由PSW的RS0和RS1确定
C. interrupt是C51的关键词，不能作为变量名
D. using也是C51的关键词，不能省略
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答案
D
解析
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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】
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25. _______ are you going to the School Uniform Exhibition, Amy ?
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【单选题】
( ) 26. Where does the writer of "The little Prince" come from?
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A. A
B. B
C. C
D. D
【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
A. A
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【单选题】
( ) 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．
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？
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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
