1·I was wakened by a knock at the door.
敲门声把我吵醒了。
—— 《牛津词典》
2·They heard a knock at the front door.
他们听到前门有一敲门声。
—— 《柯林斯英汉双解大词典》
3·They were interrupted by a knock at the door.
他们被敲门声打断了。
—— 《牛津词典》
4·Late that evening, there was a knock at the door.
那天深夜，有人敲过门。
—— 《牛津词典》
5·I'm sure luck will knock at your door!
我相信幸运会敲你的门！
6·There came a crazy knock at the doctor's office door.
医生办公室传来一阵疯狂的敲门声。
7·You're supposed to knock at the door and wait before entering the office.
进办公室之前，你应该先敲门然后等着。
8·There was a knock at the door.
门外传来敲门声。
9·Suddenly there was another knock at the door.
突然，又有人敲门。
10·Who would knock at his own door if he was staying alone?
如果一个人呆着，谁会去敲自己的门呢？