Korean Can Grammar: Patterns, Rules and Examples

Listen to the most common pattern, which the next section explains.

What Is Korean Can Grammar?

Korean can grammar is the set of sentence endings that say what a person can do, may do, knows how to do, cannot avoid or finds worth doing. English uses one word, "can", for several of these ideas. Korean uses five different patterns, and each has its own lesson.

All five follow the same frame. The verb takes the modifier ending -(으)ㄹ, which is -ㄹ after a vowel and -을 after a consonant. In four patterns a dependent noun follows (수 "way, possibility" or 줄 "how"), and a closing word ends the sentence. A dependent noun (의존 명사) is a noun that cannot stand alone. In the fifth, the helper adjective 만하다 ("be worth") follows directly. After -(으)ㄹ, the next sound is pronounced tense, so 수 is said [쑤] and 줄 is said [쭐]. This follows Article 27 of the standard pronunciation rules (표준 발음법) of the 국립국어원 (National Institute of Korean Language).

The table uses the same verb, 읽다 ("read"), for all five rows, so you can see that only the middle changes. The next section gives a route through the lessons.

Which Pattern Should You Learn First?

Learn -(으)ㄹ 수 있다/없다 first, then -(으)ㄹ 줄 알다/모르다, and then the three B1 patterns in any order. The first one is the most common and the base for the rest. One pattern is at A1, one is at A2, and three are at B1.

1. Stage 1 (A1): -(으)ㄹ 수 있다/없다 gives you "can" and "cannot".
2. Stage 2 (A2): -(으)ㄹ 줄 알다/모르다 adds "know how to".
3. Stage 3 (B1): -(으)ㄹ 수도 있다 adds "might", -(으)ㄹ 수밖에 없다 adds "have no choice but to", and -(으)ㄹ 만하다 adds "worth doing".

A learner who already says 갈 수 있어요 can start at stage 2. A learner who is new to verb stems should read the Beginner Grammar list first. The next section describes each pattern.

The Patterns, Grouped by Meaning

Each pattern below has a short description, one example sentence with Revised Romanization (RR, the official Latin spelling, shown only as an aid) and audio. The first two are beginner patterns, and the last three are intermediate.

Beginner Patterns

-(으)ㄹ 수 있다/없다 (can / cannot)

This lesson teaches the basic pattern for ability, possibility and permission. It covers the forms for vowel stems, consonant stems and irregular stems. Example: 저는 한국어를 읽을 수 있어요. (jeoneun hangugeoreul ilgeul su isseoyo.) [저는 한구거를 일글쑤 이써요] "I can read Korean."

-(으)ㄹ 줄 알다/모르다 (know how to / don't know how to)

This lesson teaches the pattern for a learned skill. Its negative is 모르다, and its past form shows what you knew how to do. Example: 저는 운전할 줄 알아요. (jeoneun unjeonhal jul arayo.) [저는 운전할쭐 아라요] "I know how to drive."

Intermediate and Advanced Patterns

-(으)ㄹ 수도 있다 (it might be that, may)

This lesson teaches the pattern for a possibility that is not certain. The particle 도 softens 수 있다 from "can" to "might". Example: 비가 올 수도 있어요. (biga ol sudo isseoyo.) [비가 올쑤도 이써요] "It might rain."

-(으)ㄹ 수밖에 없다 (have no choice but to)

This lesson teaches the pattern for something that cannot be avoided. It uses 밖에 ("nothing but"), which needs a negative closing word. Example: 길이 막혀서 늦을 수밖에 없어요. (giri makyeoseo neujeul subakke eopseoyo.) [기리 마켜서 느즐쑤바께 업써요] "The road is jammed, so I have no choice but to be late."

-(으)ㄹ 만하다 (worth doing)

This lesson teaches the pattern for something that deserves the effort, such as a film worth watching. Here 만하다 is itself the closing word, so no 있다 or 없다 follows. Example: 이 영화는 볼 만해요. (i yeonghwaneun bol manhaeyo.) [이 영화는 볼 만해요] "This film is worth watching."

The next section helps you tell the look-alike patterns apart.

How Do You Choose between Look-Alike Patterns?

Choose by asking what the sentence says: can you, do you know how, might it happen, must it happen, or is it worth it? The five patterns are easy to mix up because they share a frame. The table puts them side by side with the same verb.

Two warnings help most. First, -(으)ㄹ 수 있다/없다 expresses both ability ("I can swim") and possibility or permission ("it is possible to ..."), while -(으)ㄹ 줄 알다/모르다 is only about a learned skill. The side-by-side lesson is -(으)ㄹ 수 있다 vs -(으)ㄹ 줄 알다. Second, -(으)ㄹ 수 있다 and -(으)ㄹ 만하다 look alike, but 수 있다 describes what is possible, and 만하다 describes what is worth doing. For the negative "cannot" in the sense of an outside block, see 못 can't in Korean. The next section covers practice.

Where Can You Practise?

Practise by taking one verb and putting it through all five patterns, as in the table above. Every lesson in this set ends with a practice set and an answer key.

• Test your grammar in the Grammar Quizzes.
• Build and reorder sentences in the Korean Sentence Builder.
• Compare confusing pairs on the Confusing Grammar Compared hub.
• Plan by level with the Beginner Grammar and Intermediate Grammar lists.

A short routine works well: say one sentence a day, such as 저는 ___ 수 있어요, then switch the closing pattern to 줄 알아요. The next section sets the limits of this set.

What Does This Section Not Cover?

This set covers five patterns of ability, possibility and worth. It does not cover wishes, duties, guesses or other sentence endings, and it does not cover the grammar that builds them. Those live in other places.

• Other endings are grouped in Korean sentence endings.
• Negative forms such as 못 and -지 못하다 are in Korean negation.
• Tenses are in Korean tenses, and the modifier forms behind -(으)ㄹ are in noun modifiers.
• Politeness is in speech levels.

For the wider map, return to Korean Grammar.

Frequently Asked Questions

How do I say "I can" in Korean?

Add -(으)ㄹ 수 있어요 to a verb stem: 읽을 수 있어요 means "I can read", and 갈 수 있어요 means "I can go". Use ㄹ after a vowel and 을 after a consonant. The pattern covers ability, possibility and permission, so it is the most common way to say "can" in Korean.

How do I say "cannot" in Korean?

For "cannot", change 있어요 to 없어요: 읽을 수 없어요 means "I cannot read". The short form 못 is also common: 못 읽어요. For a missing skill, use 줄 모르다: 수영할 줄 몰라요 means "I don't know how to swim". The three differ in nuance, so check the lessons.

What is the difference between ability and know-how in Korean?

Ability and permission use -(으)ㄹ 수 있다: you are able, or the situation allows it. Know-how uses -(으)ㄹ 줄 알다: you learned the skill. A person who drank alcohol cannot drive today (운전할 수 없어요) but still knows how to drive (운전할 줄 알아요). Only the first can express permission.

Do all five patterns use the same verb form?

Yes. All five attach to the verb stem with the modifier ending -(으)ㄹ, which is -ㄹ after a vowel and -을 after a consonant. Then 수 or 줄 with a closing verb, or 만하다, follows. Irregular stems change as they do before other 으-endings, so 듣다 gives 들을 and 돕다 gives 도울.