-지 않다: The Long Form of 안, and When It Fits Better

Korean has two ways to negate a verb. They mean the same thing.

안 가요 — I’m not going. (short, spoken)
가지 않아요 — I’m not going. (long, written)

Both are correct. The difference is register, not meaning.

Building the long form

Strip -다, add -지 않다, conjugate 않다 like any verb:

가다   →  가   →  가지 않아요
춥다   →  춥   →  춥지 않아요
먹다   →  먹   →  먹지 않아요
공부하다      →  공부하지 않아요

No consonant/vowel decision, no irregulars. It attaches to anything.

Past tense goes on 않다, not on the main verb:

가지 않았어요 — I didn’t go.
갔지 않아요

Which to use

안 — conversation, almost always. Shorter, and what you will actually hear. -지 않다 — writing, reports, formal speech, and when you want a slightly softer landing.

That last point is real but subtle. 좋지 않아요 lands a touch gentler than 안 좋아요, the way “that isn’t ideal” sits softer than “that’s bad.” Do not overthink it as a beginner.

The 하다 trap

This is the mistake worth getting right now.

하다 verbs are secretly two words — a noun plus 하다. So 안 goes inside:

공부하다  →  공부 안 해요     ✅
          →  안 공부해요      ❌

운동하다  →  운동 안 해요     ✅
전화하다  →  전화 안 해요     ✅

Ordinary one-word verbs take 안 in front as expected:

가다  →  안 가요    ✅
먹다  →  안 먹어요  ✅

The long form sidesteps this entirely — 공부하지 않아요 needs no decision. That alone makes it worth knowing early.

Two verbs that refuse both

알다 (to know) and 있다 (to exist / to have) have their own negative words:

몰라요 — I don’t know.
없어요 — There isn’t / I don’t have.

Speakers do not use 안 알아요 or 안 있어요 for these. This is the same situation as 이/가 아니다, where 이다 has 아니다 rather than a negated form — Korean keeps a few dedicated negative words instead of building them.

Not the same as 못

Worth separating now, even though it comes later in the course.

안 가요 — I’m not going. (I chose not to)
못 가요 — I can’t go. (something prevents me)

안 is about will. 못 is about ability or circumstance. Turning down an invitation with 안 가요 can sound blunt — 못 가요 lets the reason be outside you, which is why it is the kinder refusal.

The short version

Use 안 when you speak, -지 않다 when you write, and remember that 하다 verbs split. Everything else follows.