무슨 짓을 했는지

what you did

→ 무슨
phrase Very common #1,201
what you did Usually refers to someone’s questionable, troublesome, or shocking actions. 무슨 짓을 하다 can also mean “to do what on earth” or “to do something terrible.”
KO: 네가 어제 무슨 짓을 했는지 알아?
EN: Do you know what you did yesterday?

무슨 짓을 했는지 몰라?

Don't you know what you've done?

— 히든 (2005)

네가 무슨 짓을 했는지 알아?

Do you know what you did?

— 부고니아 (2025)

너희가 무슨 짓을 했는지 봐라

Look at what you've done.

— 너자 2 (2025)

무슨 짓을 했는지 모르겠지만 이건 정말 아닌 것 같네

I don't know what John did, but this really doesn't seem right.

— 맨 프럼 어스 (2007)