i was watching tv when i heard the door(knocking)
题目
i was watching tv when i heard the door(knocking)
i was watching tv when i heard someone(knocked)at the door
两个knock形式对吗?
答案
I was watching tv when i heard the door(knocked).
听到门被敲,要用被动
I was watching tv when i heard someone(knocking)at the door
有人敲门,是主动,要用knocking
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