Ability (~ㄹ 수 있다/없다)

Expressing Ability: -ㄹ/을 수 있다

The pattern -ㄹ/을 수 있다 is how Korean expresses "can" or "be able to." The word 수 literally means "way" or "means," so the pattern literally translates to "there is a way to do (verb)."

Formation Rules

The ending depends on whether the verb stem ends in a vowel or consonant:

Conjugation Table

Example Sentences

Expressing Inability: -ㄹ/을 수 없다

To say "cannot," simply replace 있다 with 없다:

Example Sentences

못 vs -ㄹ 수 없다

Korean has two ways to say "cannot": the adverb 못 placed before the verb, and the grammar pattern -ㄹ/을 수 없다. They are largely interchangeable but have subtle differences.

Comparison Examples

Note on 하다 verbs: With compound verbs like 운전하다, 못 goes between the noun and 하다: - 운전 못 해요. (Cannot drive.) -- NOT 못 운전해요.

Ability vs Possibility

The pattern -ㄹ/을 수 있다 can express both ability (a skill you have) and possibility (whether something is feasible):

Context makes the meaning clear in most cases.

Questions with -ㄹ 수 있다

To ask "Can you...?", simply add the question intonation or marker:

Speech Level Conjugation

Common Mistakes

Practice

Express these abilities in Korean:

1. I can read Korean. → 한국어를 읽을 수 있어요.
2. I cannot cook. → 요리할 수 없어요. / 요리 못 해요.
3. Can you swim? → 수영할 수 있어요?
4. She cannot come today. → 오늘 올 수 없어요.