Listen to the sentence that shows the simplest aspect form, a state that stays.
The next section defines the topic.
What Is Korean Aspect?
Korean aspect is the way a verb ending shows whether an action is ongoing, finished, still in effect or part of your experience. Tense places an event in time: past, present or future. Aspect describes the shape of the event, such as "it happened and the result stays". Korean uses helper verbs and endings for this job.
Three forms cover the first steps:
- A state that stays. -아/어 있다 turns an action into its lasting result. 열리다 means "to open", and 열려 있다 means "to be open".
- Life experience. -(으)ㄴ 적이 있다 says you have done something at least once. 가다 becomes 간 적이 있다, "have been".
- A cut-off past. -았었- marks a past state or event that is no longer connected to now. 살았다 becomes 살았었다, "once lived".
A helper verb (보조 용언) is a verb that follows another verb to add meaning: 있다 is the helper in -아/어 있다. In -(으)ㄴ 적이 있다, 있다 is the ordinary verb "to exist" after the noun 적 ("occasion"). The wider area of time is described in Korean tenses. The next section gives a route through the lessons.
Where Should You Start with Korean Aspect?
Start with the state form, then experience, then the two past-perfect lessons. The order moves from the simplest pattern to the most subtle contrast.
- Stage 1: a state that stays. Read -아/어 있다 state.
- Stage 2: life experience. Read -(으)ㄴ 적이 있다 experience.
- Stage 3: the cut-off past. Read past perfect -았었-.
- Stage 4: the comparison. Read -았- vs -았었-.
Who can skip ahead? A learner who already uses the past tense -았/었- with confidence can start at stage 2. A learner who has not met the past tense should read past tense -았/었- first, because every lesson in this set builds on it. The next section describes each lesson.
Browse by Topic
Each published lesson below has a short description, one example sentence with Revised Romanization (RR, the official Latin spelling, shown only as an aid) and audio.
-아/어 있다 State
The state lesson teaches how to describe a state that remains after an action, using intransitive and passive verbs. It also compares the state with the action in progress, -고 있다. Example: 의자에 앉아 있어요. (uijae anja isseoyo.) "I am sitting on the chair." Spoken [의자에 안자 이써요].
-(으)ㄴ 적이 있다 Experience
The experience lesson teaches how to say you have done something at least once, and how to say you never have. It covers the past modifier, ㄹ-stems and the trying form -아/어 본. Example: 한국에 간 적이 있어요. (hanguge gan jeogi isseoyo.) "I have been to Korea." Spoken [한구게 간 저기 이써요].
Past Perfect -았었-
The past-perfect lesson teaches the doubled past marker -았었-, which marks an event or state that is finished and cut off from the present. Example: 어릴 때 피아노를 배웠었어요. (eoril ttae pianoreul baewosseosseoyo.) "I learned the piano when I was little." Spoken [어릴 때 피아노를 배워써써요].
-았- vs -았었-
The comparison lesson puts the plain past and the past perfect side by side on the same verbs. It shows when each one fits and what the extra 었 adds. Example: 서울에 살았었어요. (seoure sarasseosseoyo.) "I used to live in Seoul (but not now)." Spoken [서우레 사라써써요].
The next section helps you choose a lesson for your own sentence.
Which Lesson Fits Your Sentence?
Match the sentence you want to say to the lesson in the table.
| If you want to say... | Open | Why |
|---|---|---|
| "The door is open" or "The light is on" | -아/어 있다 state | the result of an action stays |
| "I am sitting" or "She is standing" | -아/어 있다 state | posture is a lasting state |
| "I have been to Korea" | -(으)ㄴ 적이 있다 experience | experience at least once |
| "I have never tried kimchi" | -(으)ㄴ 적이 있다 experience | 적이 없다 means never |
| "I used to live there, but not now" | past perfect -았었- | the state is cut off from now |
| "Is it -았어요 or -았었어요?" | -았- vs -았었- | the two forms compared |
The next section shows the most useful contrast in the set.
How Do -았- and -았었- Differ at a Glance?
-았- reports an ordinary past event, and -았었- adds that the situation is finished and no longer connected to now. The two forms use the same stem and differ by one syllable.
| Verb | With -았- | With -았었- |
|---|---|---|
| 살다 (live) | 서울에 살았어요. I lived in Seoul. | 서울에 살았었어요. I lived in Seoul once (not now). |
| 배우다 (learn) | 피아노를 배웠어요. I learned the piano. | 피아노를 배웠었어요. I learned the piano long ago. |
| 가다 (go) | 부산에 갔어요. I went to Busan. | 부산에 갔었어요. I went to Busan (and came back). |
A sentence with -았- can leave the present open, and a sentence with -았었- usually closes it. The -았- vs -았었- lesson compares the two with audio examples and practice. The next section lists the mistakes to avoid first.
Which Mistakes Come First?
Three mistakes appear in most beginner sentences in this area.
- Attaching -아/어 있다 to a transitive verb. Saying 문을 열어 있어요 is wrong. Say 문이 열려 있어요 for the state of the door.
- Using the wrong modifier in 적이 있다. Saying 갈 적이 있어요 for a past experience is wrong. Say 간 적이 있어요, with the past modifier -(으)ㄴ.
- Using -았었- for every past event. Saying 어제 밥을 먹었었어요 sounds odd. Use -았- for ordinary past events.
Each lesson in the set explains these in detail. The next section shows what the set leaves out.
What Does This Set Not Cover?
The Korean aspect set covers states, experience and the past perfect. It does not cover the progressive -고 있다, which belongs to Korean progressive forms, or the plain past, which sits in past tense -았/었-. It does not teach the verb endings in general.
The Korean text and spoken forms on this page were machine-generated and reviewed and signed off by Min-ji Park on 15 October 2026. The next section shows how to practise.
How Do You Practise Korean Aspect?
Practise Korean aspect by turning plain sentences into state, experience and past-perfect sentences, and checking them against a key. A short routine works well across a week.
- Read one lesson and say its model sentences aloud with the audio.
- Describe your room with five state sentences, such as 창문이 열려 있어요.
- Write three experience sentences, such as 부산에 간 적이 있어요.
- Take the grammar quizzes to check the pattern.
- Review the forms with the grammar flashcard decks.
- Print a grammar worksheet and fill it in by hand.
- Check how a verb changes with the Korean verb conjugator.
Each published lesson ends with a practice set and an answer key, so you can check your work immediately. After finishing the set, return to Korean tenses and continue to the other lessons in Korean grammar.
Frequently Asked Questions
How do I say "I have been to Korea"?
Say 한국에 간 적이 있어요. The pattern is the past modifier of the verb, the noun 적, and 있어요. It says you have the experience at least once and gives no date. To say you have never been, use 없어요: 한국에 간 적이 없어요. The lesson on -(으)ㄴ 적이 있다 teaches the full pattern.
What does -았었- add to -았-?
-았었- marks a past event or state that is finished and cut off from now. 서울에 살았어요 says only that you lived in Seoul. 서울에 살았었어요 adds that this was long ago or is no longer true. It is common for earlier habits, former homes and past states that changed.
How do I choose between -았- and -았었-?
Use -았- for an ordinary past event. Use -았었- when you want to stress that the situation is over and no longer connected to the present. If you are unsure, -았- is safe, because -았었- adds a claim about the present that may be wrong.
Which lesson in aspect and experience should I read first?
Start with -아/어 있다, the state form, because it uses a simple pattern and appears in daily speech: 문이 열려 있어요. Then read -(으)ㄴ 적이 있다 for experience, then past perfect -았었-, and finally the comparison of -았- with -았었-. The order moves from simple states to subtle past contrasts.