题目内容
---who______it be that is knocking at the door?
---It_______be Father, but I’m not sure.
| A．can, must | B．can, may | C．must, can | D．may, must |
B
解析试题分析：句意：--敲门的会是谁？---有可能是父亲，但是我不是很肯定。第一空填can，用于否定或疑问句表示推测“可能”，第二空填may，因为说话人不是很确定，but I’m not sure.所以选B。
考点：考查情态动词
No student go out of school for snacks during the break without the teacher’s permission.
| A．will | B．must | C．shall | D．may |
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| A．must not | B．won’t | C．can’t | D．may not |
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| A．can't | B．don’t | C．won’t | D．mustn’t |
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| A．must | B．can | C．shall | D．need |
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| A．shall | B．must |
| C．may | D．will |
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| A．must | B．might | C．can | D．would |
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| A．must have asked |
| B．could have asked |
| C．would have asked |
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| A．will | B．may |
| C．should | D．can |