Just when she was going to bed, there was a knock at the door.

正当她要上床睡觉时，有敲门声。

Did you hear a knock at the door?

你听到有人敲了一下门吗?。

At that moment there came a knock at the door.

正在这时，有人敲门了。

A knock AT the door interrupted his concentrATion.

敲门声打断了他的专心思考。

A knock at the door interrupted his concentration.

敲门声打断了他的专心思考。

There is a knock at the door. It’s Ralph, a Bible sales man.

门外有人敲门，是个卖圣经的人，叫做Ralph，在门口长篇大论了一番。

Had she fallen asleep when a knock at the door awakened her.

她刚一睡着，这时一阵敲门声把她弄醒了。

She was squeezing juice out when she heard a knock at the door.

她正在榨果汁，这时听到有人敲门。

In a minute or so there's a knock at the door. It's Van Norden.

过了约摸才一分钟便有人敲门，是范诺登，他惊慌不安。

In a few minutes, there was a knock at the door and a waiter entered.

几分钟后，传来了敲门声，一个侍者走了进来。