题目内容
【题目】Listen! Someone __________ at the door. I'll go to see who it is.
A. has knocked
B. is knocking
C. are knocking
D. knocks
【答案】B
【解析】句意:听!有人在敲门。我去看看是谁。listen听,用于现在进行时;someone为单数第三人称。
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题目内容
【题目】Listen! Someone __________ at the door. I'll go to see who it is.
A. has knocked
B. is knocking
C. are knocking
D. knocks
【答案】B
【解析】句意:听!有人在敲门。我去看看是谁。listen听,用于现在进行时;someone为单数第三人称。