You need to knock the door?

[kwfine]

Dear teachers,

I went to see a doctor in a clinic last week.
I was sitting in the waiting room and I saw a kid rush into the doctor's room when it was his turn to see the doctor.
The nurse was not happy with that kid's behaviour and told him loudly:
"You need to knock the door first and asked for permission to come in"

Is it correct to say "You need to knock the door"?
or is an preposition needed in this case?

Please help, teachers.

Thank you

Kitty

[easybreakable]

**** Learner


- A preposition is needed here (on/at).

- using the word "knock" without a preposition might give another meaning. (if something is knocking like an engine, it means it's producing a high sound).

[rainous]

- using the word "knock" without a preposition might give another meaning. (if something is knocking like an engine, it means it's producing a high sound).

You mean it could almost sound like the nurse is telling the kid to knock down the door
as in some sort of a heist situation? That would be hilarious.