갔었어

went, had gone, had gone bad, had gone off

→ 가다
갔 Past tense + 었 Past tense + 어 Informal non-polite ending
verb · informal, pluperfect tense Uncommon #10,513
went, had gone Past form of 가다; often used for something that happened in the past and is no longer the case.
KO: 지난주에 서울에 갔었어.
EN: I went to Seoul last week.
had gone bad, had gone off Used colloquially in the expression 맛이 가다, meaning that food has spoiled or lost its good taste.
KO: 우유가 맛이 갔었어.
EN: The milk had gone bad.
Conjugation of 가다

어느 병원 갔었어?

Which hospital did you go to?

— 쿵푸 허슬 (2004)

난 보스턴에 꽤 자주 갔었어.

I used to go to Boston quite often.

어제 갔었어

I went there yesterday.

— 미스틱 리버 (2003)

너 뉴질랜드 갔었어?

Have you ever been to New Zealand?

— 20th Century Girl (2022)

언제 목사님 한테 갔었어?

When did you go see the pastor?

— 하얀 리본 (2009)

맛이 갔었어

It had gone bad.

— 라라랜드 (2016)

파라비치노 대령 얘기 들으러 갔었어

I went to hear about Colonel Paravicino.

— 레오파드 (1963)

그 집에 갔었어

I went to that house.

— 히든 (2005)