Korean Past Tense: Complete Guide to Conjugation & Usage
Introduction to Korean Past Tense
The past tense in Korean is used to describe actions, events, or states that have already occurred. Unlike English, which uses auxiliary verbs like "did" or changes verb forms irregularly, Korean past tense follows a systematic pattern of adding specific endings to verb and adjective stems. Understanding how to use past tense in Korean is essential for expressing completed actions, sharing experiences, and telling stories.
Korean has two main speech levels you'll encounter when learning past tense: the polite informal level (해요체) used in everyday conversation, and the formal level (합니다체) used in professional or formal settings. Both follow predictable conjugation patterns once you understand the basic rules.
Formation: Korean Past Tense Conjugation
Korean past tense conjugation involves adding the past tense marker -았/었/였 to the verb or adjective stem, followed by the appropriate ending for your speech level. The choice between -았, -었, or -였 depends on the vowel in the final syllable of the stem.
Basic Rules
| Stem Vowel | Past Tense Marker | When to Use |
|---|---|---|
| ㅏ or ㅗ | -았- | Stems ending in bright vowels (양성모음) |
| Other vowels | -었- | Stems ending in dark vowels (음성모음) |
| 하다 verbs | -였- (했) | All 하다 verbs contract to 했 |
Polite Informal Past Tense (-았/었/였어요)
| Dictionary Form | Stem | Past Tense | Meaning |
|---|---|---|---|
| 가다 (to go) | 가- | 갔어요 | went |
| 오다 (to come) | 오- | 왔어요 | came |
| 먹다 (to eat) | 먹- | 먹었어요 | ate |
| 마시다 (to drink) | 마시- | 마셨어요 | drank |
| 공부하다 (to study) | 공부하- | 공부했어요 | studied |
| 예쁘다 (to be pretty) | 예쁘- | 예뻤어요 | was pretty |
Formal Past Tense (-았/었/였습니다)
| Dictionary Form | Past Tense (Formal) | Meaning |
|---|---|---|
| 가다 | 갔습니다 | went |
| 먹다 | 먹었습니다 | ate |
| 하다 | 했습니다 | did |
Vowel Contraction Rules
When the stem ends in a vowel, contraction often occurs:
- 가 + 았 → 갔 (가다 → 갔어요)
- 오 + 았 → 왔 (오다 → 왔어요)
- 마시 + 었 → 마셨 (마시다 → 마셨어요)
- 하 + 였 → 했 (하다 → 했어요)
- 배우 + 었 → 배웠 (배우다 → 배웠어요)
Usage: When and How to Use Past Tense in Korean
Understanding how to use past tense in Korean goes beyond simple conjugation. Here are the main contexts where past tense is used:
1. Completed Actions
Use past tense for actions that have been finished:
어제 영화를 봤어요. — I watched a movie yesterday.
2. Past States or Conditions
Describe how things were in the past:
날씨가 추웠어요. — The weather was cold.
3. Past Experiences
Talk about things you've done before:
한국에 가 봤어요. — I've been to Korea (I tried going to Korea).
4. Reported Speech and Storytelling
Narrate events that happened:
그 사람이 도착했어요. — That person arrived.
5. With Time Expressions
Past tense naturally pairs with time expressions like:
- 어제 (yesterday)
- 지난주 (last week)
- 작년 (last year)
- 아까 (earlier, a while ago)
- 전에 (before, ago)
Korean Past Tense Examples
Here are practical Korean past tense examples showing various verbs and contexts:
| Korean | English Translation | Notes |
|---|---|---|
| 저는 아침을 먹었어요. | I ate breakfast. | 먹다 → 먹었어요 |
| 친구를 만났어요. | I met a friend. | 만나다 → 만났어요 |
| 한국어를 공부했어요. | I studied Korean. | 하다 verb → 했어요 |
| 어제 비가 왔어요. | It rained yesterday. | 오다 → 왔어요 |
| 그 영화가 재미있었어요. | That movie was interesting. | Adjective: 재미있다 → 재미있었어요 |
| 서울에서 살았어요. | I lived in Seoul. | 살다 → 살았어요 |
| 커피를 마셨어요. | I drank coffee. | 마시다 → 마셨어요 |
| 책을 읽었습니다. | I read a book. (formal) | 읽다 → 읽었습니다 |
Common Mistakes
When learning Korean past tense conjugation, learners often make these errors:
1. Forgetting Vowel Contraction
Incorrect: 가았어요
Correct: 갔어요
When the stem vowel and past tense marker combine, they contract. Don't write them separately.
2. Using Wrong Vowel Harmony
Incorrect: 먹았어요 (using -았 with a dark vowel stem)
Correct: 먹었어요
Remember: only stems with ㅏ or ㅗ as the final vowel use -았-. All others use -었-.
3. Forgetting 하다 Contraction
Incorrect: 공부하였어요
Correct: 공부했어요
While 하였어요 is technically correct, native speakers almost always use the contracted form 했어요.
4. Confusing Irregular Verbs
Some verbs have irregular stems that change before the past tense marker:
- 듣다 (to listen) → 들었어요 (ㄷ → ㄹ)
- 걷다 (to walk) → 걸었어요 (ㄷ → ㄹ)
- 돕다 (to help) → 도왔어요 (ㅂ → 오/우)
- 춥다 (to be cold) → 추웠어요 (ㅂ → 우)
5. Mixing Speech Levels
Incorrect: 갔습니요
Correct: 갔습니다 (formal) or 갔어요 (polite informal)
Don't mix endings from different speech levels. Choose one and use it consistently.
6. Overusing Past Tense with 있다/없다
When describing possession or existence that continues to the present, Korean often uses present tense where English might use past:
Less natural: 저는 고양이가 있었어요. (I had a cat — implies you no longer have it)
More natural: 저는 고양이가 있어요. (I have a cat — if you still have it)