What is the difference between "knock on the door" and "knock at the door"? — Kylie, Hong Kong
The phrase "knock on the door" usually uses "knock" as a verb. Knocking on a door is using the knuckles of the hand to hit a door to get the attention of someone on the other side of the door. The phrase "knock at the door" uses "knock" as a noun. A knock at the door is the sound that someone hears when another person hits a door with their knuckles.
He knocked on the door and waited for someone to answer.
You have to knockon the door because the doorbell is broken.
He walked up to the door and knocked (on it).
She heard someone knocking (on the door), so she opened it to see who was there.
He was startled by a knock at the door. [=he was startled by the sound of someone knocking]
They were just settling in for the night when they heard a knock at the door.
They heard a loud knock at the door from the living room.
She heard a knock at the door, so she opened it to see who was there.
Sometimes "knock on the door" is used like "knock at the door" where "knock" is a noun, but this is less common.
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