Advanced Past Tense (-았/었었다, -던)

Think of -았/었었다 as a "double past" tense. It adds an extra layer of pastness to an action or state, emphasizing that it is completely finished and has no connection to the present.

Its main function is to talk about:

A discontinued state: Something that was true in the past but is no longer true.

A past experience: An event that happened once (or more) in the past and is now just a memory.

For example, 저는 학생이었어요 (I was a student) is a simple fact about the past. However, 저는 학생이었었어요 adds the nuance of "I was a student back then, but I'm definitely not one now."

Examples:

저 건물은 서점 이었었어요 .

That building used to be a bookstore (but it isn't anymore).

작년에 제주도에 갔었어요 .

I went to Jeju Island last year (a completed past experience).

Key takeaway: Use -았/었었다 when you want to strongly contrast a past situation with the present.

The ending -던 is used to modify a noun that follows it. It attaches to a verb stem and looks back at a past action or state from the perspective of the present. It's like saying "the noun that I used to..." or "the noun that I was...-ing."

Common Uses of -던

Habitual or Repeated Action: Describing something you used to do regularly.

제가 자주 가던 카페

The cafe I used to go to often

Ongoing State: Describing a state that continued for some time in the past.

제가 살던 동네

The neighborhood where I used to live

Incomplete Action: Describing an action that was in progress but was interrupted or not finished.

제가 읽던 책

The book I was reading (and haven't finished)

While both -던 and -았/었던 modify nouns by describing past events, they have a crucial difference in nuance related to completion and frequency.