줄 몰랐다

didn't know that …

→ 줄
phrase Rare #28,922
didn't know that … Used after a verb or adjective to say that someone didn't know or expect something to be the case.
KO: 겨울이 이렇게 일찍 올 줄 몰랐다.
EN: I didn't know winter would come so early.

그녀가 바로 내 뒤에 서 있는 줄 몰랐다.

I didn't realize she was standing right behind me.

톰은 메리가 늦을 줄 몰랐다

Tom didn't know that Mary would be late.

이렇게 많이 울 줄 몰랐다

I didn't know I would cry this much.

— 중경삼림 (1994)