이라는 걸

that it is

→ 이다

phrase Rare #18,357

that it is A contracted form of 이라는 것을, used to mark a clause stating that something is a particular noun or identity. It commonly appears before verbs such as 알다 (to know), 모르다 (to not know), and 이해하다 (to understand).

KO: 그가 우리 선생님이라는 걸 몰랐어요.

EN: I didn't know that he was our teacher.

톰은 매우 게으른 소년 이라는 걸 압니다.

I know Tom is a very lazy boy.

중요한 배역 이라는 걸 클라우디아도 아나?

Does Claudia know that this is an important role?

— 8과 1/2 (1963)