[KNOCK on door]
The Big Bang Theory Season 12, Episode 5
Oh, don't be. You get your hopes up,
I KNOCK them down,
The Big Bang Theory Season 10, Episode 6
[KNOCK ON DOOR]
The Big Bang Theory Season 8, Episode 6
Yeah, KNOCK it off, Howard!
The Big Bang Theory Season 7, Episode 13
You set 'em up, I KNOCK 'em down.
Good job.
The Big Bang Theory Season 10, Episode 17