Learn Korean for Free | Beginner Korean Grammar #25
The bus was late, so you arrived late. You went to a café and drank coffee. -아서/어서 connects these naturally related parts.
What Does A/V-아서/어서 Mean?
Use -아서/어서 to give a reason or cause, and with some action verbs to show a closely connected sequence. The first clause explains or leads into the second.
The Rule
Stems with ㅏ or ㅗ usually take -아서: 작다 → 작아서, 가다 → 가서. Other vowels take -어서: 먹다 → 먹어서, 늦다 → 늦어서. 하다 becomes 해서. The form often contracts just like the 아/어요 form.
Useful Korean Words
| Korean | English |
|---|---|
| 늦다 | to be late |
| 아프다 | to be sick |
| 배고프다 | to be hungry |
| 비싸다 | to be expensive |
| 가다 | to go |
| 만나다 | to meet |
| 피곤하다 | to be tired |
| 행복하다 | to be happy |
Korean Grammar Examples
비가 와서 집에 있어요.
It is raining, so I am at home.
배가 아파서 병원에 갔어요.
My stomach hurt, so I went to the hospital.
이 가방은 비싸서 안 사요.
This bag is expensive, so I do not buy it.
친구를 만나서 같이 점심을 먹었어요.
I met a friend and ate lunch together.
시험이 끝나서 기분이 좋아요.
The exam is over, so I feel good.
A Short Dialogue
A: 왜 늦었어요? — Why were you late?
B: 버스가 늦게 와서 늦었어요. — The bus came late, so I was late.
A: 점심은 먹었어요? — Did you eat lunch?
B: 시간이 없어서 못 먹었어요. — I had no time, so I couldn’t eat.
A Common Mistake to Avoid
Normally, do not put a past marker in the first clause for this beginner reason pattern: say 어제 아파서 학교에 못 갔어요, not 아팠어서. Also avoid using reason -아서/어서 directly before a command or suggestion; Lesson 29’s -(으)니까 is usually more suitable: 비가 오니까 우산을 가져가세요.
Quick Quiz 🎯
Connect the two parts: ① 피곤해요 + 일찍 자요. ② 날씨가 좋아요 + 산책해요. ③ 시장에 가요 + 과일을 사요. ④ 시간이 없어요 + 택시를 타요.
Answers and Explanation
① 피곤해서 일찍 자요. ② 날씨가 좋아서 산책해요. ③ 시장에 가서 과일을 사요. ④ 시간이 없어서 택시를 타요.
Try It in Your Own Life
Write two original sentences with A/V-아서/어서 about your real schedule, plans, travel, food, or Korean study. Read them aloud, then change one word or time expression and say them again. This turns the pattern into language you can use instead of a sentence you only recognize.
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