Know How To (-(으)ㄹ 줄 알다/모르다)
-(으)ㄹ 줄 알다/모르다
Expresses knowing or not knowing how to do something.
Pattern
Verb stem + -(으)ㄹ 줄 알다/모르다
Explanation
-(으)ㄹ 줄 알다 means 'to know how to do' something, while -(으)ㄹ 줄 모르다 means 'to not know how to do' something. Use -ㄹ 줄 after stems ending in a vowel and -을 줄 after consonants.
This pattern focuses on learned ability or skill: 수영할 줄 알아요 means 'I know how to swim' (I have learned to swim). It is different from -(으)ㄹ 수 있다, which expresses general possibility or ability based on circumstances: 수영할 수 있어요 means 'I can swim' (circumstances allow it).
-(으)ㄹ 줄 알다/모르다 can also express expectation: 이렇게 어려울 줄 몰랐어요 (I didn't know it would be this difficult). This usage expresses surprise at an unexpected situation. Both meanings are tested on TOPIK Level 3.
Examples
한국어를 할 줄 알아요?
Hangugeoreul hal jul arayo?
Do you know how to speak Korean?
저는 수영할 줄 몰라요.
Jeoneun suyeonghal jul mollayo.
I don't know how to swim.
피아노를 칠 줄 알아요.
Pianoreul chil jul arayo.
I know how to play the piano.
이렇게 비쌀 줄 몰랐어요.
Ireoke bissal jul mollasseoyo.
I didn't know it would be this expensive.
Common Mistakes
Wrong
수영할 줄 있어요.
Correct
수영할 줄 알아요.
Use 알다/모르다 with -줄, not 있다/없다. That would be -(으)ㄹ 수 있다/없다.
Wrong
한국어를 하는 줄 알아요.
Correct
한국어를 할 줄 알아요.
Use -(으)ㄹ (future modifier) before 줄, not -는 (present modifier).
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