Build the past exactly like the present, but insert 았/었 before 어요: ㅏ/ㅗ stems take -았어요, all others take -었어요, and 하다 becomes 했어요. The ending never changes for who did it.
Examples
- 어제 친구를 만났어요.
- I met a friend yesterday.
- 지난 주말에 영화를 봤어요.
- I watched a movie last weekend.
- 작년에 제주도에 갔어요.
- I went to Jeju Island last year.
- 어제는 아무것도 안 했어요.
- I didn't do anything yesterday.
The mistake to avoid
Marking the past twice, as in 안 갔었어요 for a simple "I didn't go" - one 았/었 is enough.
Where this fits in
지난 주말, Korean A2: Talk about the past: yesterday, last weekend, and travel memories.