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。

youdao

Pinocchio went straight to the Fairy's house, firmly resolved to knock at the door.

皮诺乔径直走到仙女家，打定主意要敲门。

youdao

It's impolite to knock at the door in that way.

那样子敲门是很不礼貌的。

youdao

So if you want to taste something good, just knock at the door.

所以如果你想要品尝美味，就都试看吧。

关于肉品市场区 - SpeakingMax英语口语达人

The 22-year-old answered a knock to the front door of her home in Third Avenue in Luton at 13:10 GMT on Thursday.

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Take some steps to prevent a repeat performance: Install a lock on your bedroom door, encourage kids to knock, play soft music or the TV for white noise at night, and schedule "private parent time" when your child knows not to disturb you.

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