If It Had Been (-았/었더라면)

-았/었더라면 expresses a counterfactual condition — something that didn't happen in the past but the speaker imagines what would have been different if it had: 일찍 출발했더라면 늦지 않았을 거예요 (If I had left early, I wouldn't have been late).

This pattern always refers to past unrealized situations and typically expresses regret. The result clause often uses -(으)ㄹ 텐데 or -(으)ㄹ 거예요 to express what would have happened.

The shorter form -았/었으면 can sometimes substitute in casual speech: 일찍 갔으면 좋았을 텐데 (It would have been nice if I had gone early). But -았/었더라면 is more explicit about the counterfactual nature.