‘-았/었더니’ is a Korean grammar pattern used to express results, discoveries, and cause-and-effect relationships that arise from past actions or states. This structure frequently conveys realization, change, or unexpected outcomes after direct experience.
Contents
1. What Does ‘-았/었더니’ Mean in Korean Grammar?
The expression ‘-았/었더니’ is used to describe a situation where a past action or state led to a subsequent realization or result. It emphasizes that the speaker’s past experience or action has a direct connection to the present outcome or understanding. In English, it can be loosely translated as “When I did (something), (I realized/discovered that)…” or “After doing (something), (I found that)…”
2. ‘-았/었더니’ Structure and Formation
Formation: Past tense verb + 더니
This structure combines a past-tense predicate with ‘더니’.
For regular verbs:
가다 (to go) → 갔다 + 더니 → 갔더니
먹다 (to eat) → 먹었다 + 더니 → 먹었더니
For 하다 verbs:
공부하다 (to study) → 공부했다 + 더니 → 공부했더니
For irregular verbs:
듣다 (to listen) → 들었다 + 더니 → 들었더니
걷다 (to walk) → 걸었다 + 더니 → 걸었더니
긋다 (to draw a line) → 그었다 + 더니 → 그었더니
낫다 (to recover) → 나았다 + 더니 → 나았더니
돕다 (to help) → 도왔다 + 더니 → 도왔더니
Example with a descriptive verb:
춥다 (to be cold) → 추웠다 + 더니 → 추웠더니
📌 Note: Although ‘춥다’ is a descriptive verb, some temporary state adjectives like ‘춥다’, ‘더웠다’, ‘아팠다’, or ‘배고팠다’ can naturally appear with ‘-았/었더니’ when they describe a change or condition that leads to a result.
3. When and How to Use ‘-았/었더니’ Grammar Pattern
‘-았/었더니’ is a Korean grammar pattern used to describe results or realizations that follow a directly experienced past action.
It links a completed situation with an observed outcome,
often implying discovery, change, or noticeable effects.
3-1. Describing a Past Action That Led to a Certain Result
This usage shows that a past action caused a specific outcome.
- 어제 늦게까지 공부했더니 오늘 너무 피곤해.
(I studied late last night, so I’m really tired today.) - 매운 음식을 많이 먹었더니 속이 아파.
(I ate a lot of spicy food, and now my stomach hurts.) - 운동을 열심히 했더니 체력이 좋아졌어.
(I exercised hard, and my stamina improved.) - 친구한테 고민을 이야기했더니 기분이 한결 나아졌어.
(I talked to my friend about my worries, and I felt much better.) - 오랜만에 한국 드라마를 봤더니 한국어 듣기가 조금 쉬워졌어.
(I watched a Korean drama after a long time, and my Korean listening improved a bit.)
3-2. Realizing a Fact After a Past Experience
Used when the speaker realizes or learns something after an experience.
- 가게에 가 봤더니 문이 닫혀 있었어.
(I went to the store and realized it was closed.) - 친구를 오랜만에 만났더니 분위기가 많이 변했더라.
(I met my friend after a long time and realized their vibe had changed a lot.) - 서울에 처음 가 봤더니 생각보다 사람들이 정말 많았어.
(I visited Seoul for the first time and realized there were way more people than I expected.) - 직접 요리를 해 봤더니 생각보다 어렵지 않았어.
(I tried cooking myself and realized it wasn’t as hard as I thought.) - 유명한 맛집에 가 봤더니 기대했던 것만큼 맛있진 않았어.
(I went to a famous restaurant and realized it wasn’t as good as I expected.)
3-3. Expressing an Unexpected Result
Used when an action leads to an unexpected or contrasting outcome.
- 날씨가 맑았더니 갑자기 비가 왔어.
(The weather was clear, but suddenly it rained.) - 음식을 조금만 시켰더니 배가 너무 고팠어.
(I ordered only a little food, but I was starving.) - 친구에게 장난을 쳤더니 진짜 화를 냈어.
(I played a joke on my friend, but they really got mad.) - 길이 한산했더니 갑자기 차가 엄청 많아졌어.
(The road was empty, but suddenly there were a lot of cars.) - 사람들한테 인기가 많았던 카페에 갔더니 너무 조용했어.
(I went to a popular café, but it was really quiet.)
3-4. Expressing a Sequence of Events
Used when one action happens first, and another follows naturally.
- 집에 도착했더니 바로 전화가 왔어.
(I arrived home, and right then, I got a call.) - 편지를 보냈더니 곧 답장이 왔어.
(I sent a letter, and soon after, I got a reply.) - 수업이 끝났더니 학생들이 다 교실을 나갔어.
(The class ended, and the students all left the classroom.) - 약을 먹었더니 금방 나았어.
(I took the medicine, and I got better quickly.) - 문을 열었더니 고양이가 들어왔어.
(I opened the door, and a cat came in.)
4. Practice Exercises: Using ‘-았/었더니’
Practice Exercises: Complete the following sentences using the correct form of ‘-았/었더니’ with the given verb in parentheses.
- 오랜만에 운동을 (하다) ____________ 온몸이 아파요.
(After exercising for the first time in a while, my whole body hurts.) - 친구에게 전화를 (걸다) ____________ 바쁘다고 해요.
(When I called my friend, they said they were busy.) - 새로운 레스토랑에 (가다) ____________ 음식이 정말 맛있었어요.
(When I went to the new restaurant, the food was really delicious.) - 밤늦게까지 공부를 (하다) ____________ 아침에 일어나기 힘들었어요.
(After studying late into the night, it was hard to wake up in the morning.) - 한국 드라마를 (보다) ____________ 한국어 실력이 늘었어요.
(After watching Korean dramas, my Korean skills improved.) - 약을 (먹다) ____________ 두통이 사라졌어요.
(After taking the medicine, my headache disappeared.) - 여행을 (가다) ____________ 스트레스가 풀렸어요.
(After going on a trip, my stress was relieved.) - 친구와 오랜만에 (만나다) ____________ 이야기할 게 많았어요.
(When I met my friend after a long time, we had a lot to talk about.) - 새 옷을 (사다) ____________ 친구가 같은 옷을 입고 있었어요.
(After buying new clothes, I found my friend wearing the same outfit.) - 일찍 (자다) ____________ 다음 날 기분이 좋았어요.
(After going to bed early, I felt good the next day.)
Answers
- 했더니
- 걸었더니
- 갔더니
- 했더니
- 봤더니
- 먹었더니
- 갔더니
- 만났더니
- 샀더니
- 잤더니
5. Korean Grammar Q&A
Common learner questions about usage restrictions and nuances.
Q1: Can I use ‘-았/었더니’ with adjectives?
Generally no, but it works with temporary state adjectives describing changing conditions.
Natural Examples:
- 날씨가 추웠더니 집에 있는 게 낫겠더라.
(It was cold, so staying home seemed better.) - 몸이 아팠더니 하루 종일 쉬게 됐어요.
(I was sick, so I ended up resting all day.)
Unnatural Example:
- 사람이 예뻤더니 사람들이 좋아했어요. ✖
(She was pretty, so people liked her.)
Key Rule:
Use with temporary states (cold, tired, sick), not permanent traits (pretty, smart).
Q2: Can the subjects be different in ‘-았/었더니’ sentences?
In most cases, no.
‘-았/었더니’ usually requires the same subject in both clauses.
Natural:
제가 공부했더니 피곤해졌어요.
(I studied, and I became tired.)
Unnatural:
제가 공부했더니 친구가 피곤해졌어요.
(I studied, and my friend became tired.)
Q3: Can ‘-았/었더니’ Describe Future Situations?
Generally, no.
This grammar is strictly tied to completed past actions.
Incorrect:
내일 운동했더니 건강해질 거예요.
(I will exercise tomorrow, and I will become healthy.)
Correct:
어제 운동했더니 몸이 좋아졌어요.
(I exercised yesterday, and my body felt better.)
Q4: Why Does ‘-았/었더니’ Sometimes Sound Like Surprise?
Because the pattern often implies:
✔ Discovery
✔ Realization
✔ Unexpected outcome
Even when the result is logical, Korean frequently carries a nuance of noticing or experiencing a change.
Example:
먹어 봤더니 생각보다 맛있었어요.
(After trying it, it was tastier than expected.)
Q5: What is the difference between ‘-았/었더니’ and ‘-고’ in Korean grammar?
‘-고’ → Neutral sequence
‘-았/었더니’ → Result / realization focus
Natural sequence:
밥을 먹고 학교에 갔어요.
(I ate and went to school.)
Result emphasis:
밥을 먹었더니 졸렸어요.
(I ate, and I became sleepy.)
Still confused about how ‘-았/었더니’ differs from similar patterns?
These guides will help you understand the subtle differences Korean learners often struggle with:
👉 How to Use -더니 in Korean Grammar
👉 -았/었더니 vs -더니 – Essential Differences
6. Key Points to Remember
- Expresses results after past actions
- Frequently conveys realization or discovery
- Often implies noticeable change
- Subject consistency is typical
- Common in cause-and-effect situations
Related Korean Grammar Patterns
These grammar patterns are frequently studied alongside ‘-았/었더니’ and help learners better understand results, realizations, and cause-and-effect relationships.
-고 보니 (Realization After Reflection)
Used when a realization occurs after reviewing or reflecting on a situation.
-아/어 보니 (Discovery After Trying)
Emphasizes learning through direct experience.
Focuses on logical reasoning rather than discovery.
-아/어서 (Cause / Background Connection)
Describes general cause relationships.
Often confused with ‘-았/었더니’ due to structural similarity.