단단하다

to be hard, solid, firm

Principal parts

관형사형Modifier
단단한
아/어Infinitive
단단해
-으니Since
단단하니
합니다Formal
단단합니다

Present

해요체Polite합니다체Formal해체Casual한다체Plain
서술Statement 단단해요단단합니다단단해단단하다

Past

해요체Polite합니다체Formal해체Casual한다체Plain
서술Statement 단단했어요단단했습니다단단했어단단했다

Future & presumptive

해요체Polite합니다체Formal해체Casual한다체Plain
-겠-Will / must be 단단하겠어요단단하겠습니다단단하겠어단단하겠다
-을 것이다Going to 단단할 거예요단단할 것입니다단단할 거야단단할 것이다

Questions

해요체Polite합니다체Formal해체Casual한다체Plain
현재Present 단단해요?단단합니까?단단해?단단하니?
과거Past 단단했어요?단단했습니까?단단했어?단단했니?

Negation

해요체Polite합니다체Formal해체Casual한다체Plain
안Not (short) 안 단단해요안 단단합니다안 단단해안 단단하다
-지 않다Not (long) 단단하지 않아요단단하지 않습니다단단하지 않아단단하지 않다

Honorific

해요체Polite합니다체Formal해체Casual한다체Plain
현재Present 단단하세요단단하십니다단단하셔단단하시다
과거Past 단단하셨어요단단하셨습니다단단하셨어단단하셨다

Modifying a noun

현재Present
단단한
과거Past
단단한
미래Future
단단할
회상Used to
단단하던

Joining clauses

-고and
단단하고
-게-ly / so that
단단하게
-어서so / and then
단단해서
-으니까since
단단하니까
-으면if / when
단단하면
-지만but
단단하지만
-는데and / but (setting up)
단단한데
-어도even if
단단해도

Sentence patterns

In real sentences

두개를 섞으면 단단한 이중 나선이 되죠.

You mix them together and they make a rigid double helix.

얼마나 단단하죠?

How hard is it?

이것이 단단한 형태입니다.

This is a stronger knot.

치아는 여러분 몸에서 가장 단단한 물질 중의 하나죠.

Your teeth are one of the hardest substances in your body.

Common questions

How do you conjugate 단단하다 in Korean?

단단하다 (to be hard, solid, firm) is 단단해요 in the polite 해요체, 단단합니다 in formal 합니다체, 단단해 in casual 반말 and 단단하다 in the plain written style. The past is 단단했어요.

What is the past tense of 단단하다?

단단했어요 in everyday polite speech, 단단했습니다 formally. It is built from the 아/어 form 단단하여 plus ㅆ, which is why an irregular stem shows its irregularity here.

Is 단단하다 irregular?

Yes — it is 여 irregular (여 불규칙). 하다 and every verb built on it: 하다 → 하여 → 해요. That is why the stem looks different in 단단하여 and 단단하니 but unchanged in 단단합니다.

What TOPIK level is 단단하다?

3급 — TOPIK 3, lower intermediate.

Dictionary form, meaning, sentence patterns, examples and audio from the 국립국어원 한국어기초사전, used under CC BY-SA 2.0 KR.

Conjugations are generated by this site's own engine and checked against the 9,380 forms the dictionary publishes on every build.