이기

being

→ 이다

이 to be + 기 Nominalizer (verb-to-noun)

auxiliary Rare #28,725

being Used to connect 이다 to words such as 때문에 (“because”) and 힘들다 (“be difficult”).

KO: 학생이기 때문에 일찍 와야 해요.

EN: Because you’re a student, you have to come early.

Conjugation of 이다

Just because you're a new mom?

— 이중 배상 (1944)

It’s hard to keep your sanity right now.

— 그레이트 뷰티 (2013)

Or is it because Seonghyeon is someone I can’t meet?

— Il Mare (2000)