-지 못하다
Cannot
-지 못하다 is a way to say 'cannot' or 'be unable to' do something.
How It Works
-지 못하다 is a key pattern for expressing inability. It's formed by attaching -지 못하다 directly to a verb stem.
Formation:
Verb Stem + -지 못하다
- 가다 (to go) → 가지 못하다 (cannot go)
- 먹다 (to eat) → 먹지 못하다 (cannot eat)
- 공부하다 (to study) → 공부하지 못하다 (cannot study)
This form is then conjugated into different tenses and politeness levels.
- Present: 가지 못해요 / 가지 못합니다
- Past: 가지 못했어요 / 가지 못했습니다
- Future: 가지 못할 거예요 / 가지 못할 겁니다
Key Distinction:
It's crucial to distinguish -지 못하다 from -지 않다.
- -지 못하다: Inability (I want to, but I can't).
- -지 않다: Lack of intention (I can, but I don't want to).
For example, '영화를 보지 못했어요' means 'I couldn't watch the movie' (maybe because I was busy), while '영화를 보지 않았어요' means 'I didn't watch the movie' (by choice).
This pattern is very similar in meaning to -ㄹ 수 없다, and they are often interchangeable.
Examples (4)
- 어제 바빠서 친구를 만나지 못했어요.
I was busy yesterday, so I couldn't meet my friend.
Word by Word: Yesterday busy so friend meet could not.
- 저는 매운 음식을 먹지 못해요.
I can't eat spicy food.
Word by Word: I spicy food eat cannot.
- 비행기 표가 없어서 제주도에 가지 못할 거예요.
There are no plane tickets, so I probably won't be able to go to Jeju Island.
Word by Word: Airplane ticket not exist so Jeju Island to go will not be able to.
- 너무 시끄러워서 공부하지 못하겠어요.
It's so noisy that I can't study.
Here, -겠- is added to express the speaker's current feeling or judgment about their inability to study.
Common Mistakes
Using -지 못하다 with adjectives (descriptive verbs).
Different Meaning이 옷이 예쁘지 못해요.Better이 옷이 예쁘지 않아요.-지 못하다 expresses the inability to perform an action, so it's used with action verbs. To negate a state or quality (adjective), you should use -지 않다 or 안.
Confusing 'cannot do' (inability) with 'do not do' (intention).
Different Meaning숙제를 하고 싶지 않아서 숙제를 하지 못했어요.Better숙제를 하고 싶지 않아서 숙제를 하지 않았어요.The incorrect sentence is awkward because it says 'I couldn't do homework because I didn't want to.' If the reason is a lack of will, you should use -지 않았어요 ('I didn't do it'). Use -지 못했어요 when an external factor prevents you, e.g., '시간이 없어서 숙제를 하지 못했어요' (I couldn't do homework because I didn't have time).
Learn This First
To express 'cannot', you need conjugation and negation knowledge.
Related Patterns
- 안/못Not
못 is the shorter, more conversational equivalent of -지 못하다. '못 가요' and '가지 못해요' both mean 'I can't go', but 못 is more common in everyday speech.
- -(으)ㄹ 수 있다/없다Can/cannot
-ㄹ 수 없다 also means 'cannot' and is very similar to -지 못하다. They are often interchangeable. For example, '가지 못해요' and '갈 수 없어요' have almost the same meaning.
- -지 않다Not
This is the direct contrast to -지 못하다. While -지 못하다 expresses inability ('cannot'), -지 않다 expresses a simple negation based on will or fact ('do not').