Korean Ability: -(으)ㄹ 수 있다 vs -(으)ㄹ 줄 알다

If you are studying Korean ability grammar, this lesson is the one to keep. You will learn how -(으)ㄹ 수 있다 / 줄 알다 works in real conversation, when to use it, and the mistakes English speakers make first. This is a Korean intermediate grammar guide with examples, romanization, and a five-minute speaking drill.

By the end you should be able to hear -(으)ㄹ 수 있다 / 줄 알다 in dramas and K-talk, then reuse it in your own sentences. Read once. Say the examples out loud. Then drill the same lines on Practice.

What -(으)ㄹ 수 있다 / 줄 알다 means

-(으)ㄹ 수 있다 is possibility or ability: I can, it’s possible. -(으)ㄹ 줄 알다 is know-how: I know how to. English “can” hides the difference. Intermediate Korean should not.

How to form it

  • Possible/able: stem + -(으)ㄹ 수 있다/없다
  • Know how: stem + -(으)ㄹ 줄 알다/모르다
  • Can’t (failure in the moment): 못 + verb
  • Permission is 어도 되다, not 수 있다

-(으)ㄹ 수 있다 / 줄 알다 examples

Use these Korean ability grammar example sentences as a speaking list. Korean first, then pronunciation, then English.

KoreanPronunciationEnglish
한글로 이메일을 쓸 수 있어요.hangeullo imeireul sseul su isseoyo.I can write an email in Hangul.
수영할 줄 알아요.suyeonghal jul arayo.I know how to swim.
오늘은 시간이 없어서 갈 수 없어요.oneureun sigani eopseoseo gal su eopseoyo.I can’t go today because I don’t have time.
젓가락 쓸 줄 몰라요.jeotgarak sseul jul mollayo.I don’t know how to use chopsticks.
길이 막혀서 제시간에 못 갔어요.giri makhyeoseo jesigane mot gasseoyo.I couldn’t get there on time because of traffic.
여기서 카드 쓸 수 있어요?yeogiseo kadeu sseul su isseoyo?Can I use a card here?

When to use it

  • Skills: 줄 알다.
  • Possibility, availability, or allowed-by-circumstance: 수 있다.
  • A specific failed attempt: 못.

Common mistakes

These are the traps English speakers hit when they translate word-for-word. Fix the pattern, not just the vocabulary.

Watch-out

❌ 수영할 수 있어요 when you mean know-how
✅ 수영할 줄 알아요

수 있다 can also mean “it’s possible for me today.” 줄 알다 is the skill.

Watch-out

❌ 수 있어요? for “may I?”
✅ 해도 돼요?

Permission is 어도 되다. 수 있다 is ability/possibility.

Watch-out

❌ 줄 수 있다 mashup
✅ Pick one pattern

쓸 수 있어요 or 쓸 줄 알아요, not 줄 수.

Mini dialogue

Read it twice. Second time, cover the English.

SpeakerKoreanPronunciationEnglish
A운전할 줄 알아요?unjeonhal jul arayo?Do you know how to drive?
B네, 할 줄 알아요. 그런데 한국에서는 아직 할 수 없어요. 면허가 없거든요.ne, hal jul arayo. geureonde hangugeseoneun ajik hal su eopseoyo. myeonheoga eopgeodeunyo.Yes, I know how. But I can’t in Korea yet — I don’t have a license.
A아, 그렇군요.a, geureokunnyo.Ah, I see.

Don’t mix these up

수 없다 is a cold impossibility. 못 is a failed try or lack in that situation. 줄을 몰라요 is missing the skill.

Five-minute Korean speaking practice

Korean speaking practice beats extra grammar notes. Do this once today, then again tomorrow without looking.

  1. Read each example slowly, Korean only.
  2. Say it at natural speed. Record yourself if you can.
  3. Cover the Korean and rebuild the sentence from English.
  4. Swap in your own details: your job, your city, your weekend.

Starter lines for today:

  • 김치 만들 줄 알아요?
  • 오늘 밤에는 만날 수 없어요.
  • 발음이 어려워서 잘 못 하겠어요.

Lesson summary

  • Pattern: -(으)ㄹ 수 있다 / 줄 알다
  • Search topic: Korean ability grammar
  • 수 있다 = can/possible. 줄 알다 = know how. 못 = didn’t manage to.
  • Say it out loud on Practice, then come back to Guides if a particle still feels sticky.

Homework

  1. List four skills with 줄 알다/모르다.
  2. List four schedule limits with 수 있다/없다.
  3. Write one 못 sentence about yesterday.

Korean ability grammar: quick answers

할 수 있을 것 같아요?

That’s a hedge: I think I might be able to. Very intermediate, very useful.

Honorific ability?

하실 수 있으세요 is extra polite. 가능하세요 is common in service talk.

Keep going

Want a path, not a single grammar point? Open Learn or browse the rest of this series in Korean intermediate.