(으)ㄹ걸 [Intermediate Grammar]

- (으)ㄹ걸

→ It is an ending added to a stem of a verb, which means a speaker regrets or sighs about what he has done already and thinks he should have done it in a different way.' As the speaker's regret or sigh is not subject to the listener, an honorific form of '요' is not added. If there are listeners, you can add '그랬어', and '그랬어요.'

Example: 

1. 그냥 내가 할걸. 괜히 부탁했다가 일이 더 번거롭게 됐네.
I should have done it by myself. Asking others is just labor in vain.

2. 이렇게 맛있는 게 많이 있는데 밥을 먹지 말고 올걸 그랬어요.
This is so delicious. I should not have eaten a meal before I came.

3. 컴퓨터를 배워 둘걸. 일하는 데 이렇게 필요할 줄 몰랐네.
I should have learned more about computers. I didn't realize how much I need them for work.

4.오늘 길이 막혀서 지하철을 탈걸.

The road is blocked today, so I will take the subway.

5.날씨가 꽤 추운데 두꺼운 옷을 입고 올걸.

The weather is quite cold. You should wear thick clothes.