How you negate depends on whether a word is an action verb or a descriptive adjective:
1. Actions (동사): Put 안 or 못 right before the verb. For -하다 action verbs, split them: 공부 안 해요 / 운동 못 해요. 2. Adjectives (형용사): Use 안 only (never 못!). And do not split -하다 adjectives: 안 친절해요, 안 따뜻해요.
Action Verb가다 (to go) · 가요 · 안 가요 · 못 가요 (unable to go)
Action -하다운동하다 (to exercise) · 운동해요 · 운동 안 해요 · 못 해요 (unable to exercise)
Adjective크다 (to be big) · 커요 · 안 커요 · No (못 커요 is wrong)
Adjective -하다친절하다 (to be kind) · 친절해요 · 안 친절해요 · No (못 친절해요 is wrong)
Why can't you use 못 with adjectives? Because 못 means *unable to do an action* due to ability or circumstance. An object cannot 'fail' at being small, warm, or pretty!
오늘은 날씨가 안 추워요.The weather isn’t cold today. / Adjective 추워요 takes 안, never 못.
치즈감자