갔었지

went, had gone, went bad

→ 가다
갔 Past tense + 었 Past tense + 지 Clause-ending marker for assertion or confirmation
verb · informal, pluperfect tense Rare #30,753
went, had gone Often used to recall or check that something happened.
KO: 우리 작년에 제주도에 갔었지?
EN: We went to Jeju Island last year, remember?
went bad Used in the expression 맛이 가다, meaning that food has spoiled.
KO: 그 우유는 이미 맛이 갔었지.
EN: That milk had already gone bad.
Conjugation of 가다

갔었지?

You went, didn't you?

— 카쉬미르의 소녀 (2015)

맛이 갔었지 그래

Yeah, it had gone bad.

— 라라랜드 (2016)