If you memorize one paradigm in Korean, make it this one. 하다 ("to do / make") is not just a common verb — it is the engine that builds thousands of others. Korean manufactures verbs and adjectives on an industrial scale by gluing 하다 onto a root, usually a Sino-Korean noun: 공부 + 하다 → 공부하다 ("study"), 사랑 + 하다 → 사랑하다 ("love"), 운동 + 하다 → 운동하다 ("exercise"). Every one of them conjugates exactly like the table below. Learn 하다 once and you have conjugated a huge slice of the entire lexicon. And the whole grid runs on a single mechanical fact worth pinning to the top of the page: the -아/어 forms of 하다 are not ×하아 or ×하어 but the contraction 하 + 여 → 해, which is why the present is 해요 and the past is 했어요.
The main grid: tense/aspect × speech level
| Tense / Aspect | 합니다체 (formal) | 해요체 (polite) | 반말 (intimate) | 한다체 (plain) |
|---|---|---|---|---|
| Present | 합니다 (hamnida) | 해요 (haeyo) | 해 (hae) | 한다 (handa) |
| Past | 했습니다 (haetseumnida) | 했어요 (haesseoyo) | 했어 (haesseo) | 했다 (haetda) |
| Future / conjecture -겠 | 하겠습니다 (hagetseumnida) | 하겠어요 (hagesseoyo) | 하겠어 (hagesseo) | 하겠다 (hagetda) |
| Future (periphrastic 할 것) | 할 겁니다 (hal geomnida) | 할 거예요 (hal geoyeyo) | 할 거야 (hal geoya) | 할 거다 (hal geoda) |
| Progressive -고 있다 | 하고 있습니다 (hago itseumnida) | 하고 있어요 (hago isseoyo) | 하고 있어 (hago isseo) | 하고 있다 (hago itda) |
The one row that is not built on 해 is the present plain form: 하다 → 한다 (a vowel stem, so -ㄴ다 as expected for the 한다체 present). Everything with an -아/어 in it — 해요, 해, 했어요, 했습니다 — comes from 하 + 여 → 해. The -겠 future and the progressive -고 있다 attach to the bare stem 하-, so they are entirely regular: 하겠어요, 하고 있어요.
저는 은행에서 일해요.
jeoneun eunhaeng-eseo ilhaeyo
I work at a bank. (일하다 → 일해요)
어제 뭐 했어요?
eoje mwo haesseoyo
What did you do yesterday? (past — 했어요)
나 벌써 숙제 다 했어.
na beolsseo sukje da haesseo
I already finished all my homework. (반말 past — 했어)
The future: -겠 vs 할 거예요
Both rows mean "will," but they are not interchangeable. -겠 leans toward the speaker's own will / intention and formal register — it is what you volunteer with, and the voice of announcements and weather reports. 할 거예요 (the prospective 것 construction) is the everyday, plan-and-prediction "will / going to." When you offer to do something on the spot, reach for -겠; when you describe a plan, reach for 할 거예요.
제가 하겠습니다.
jega hagetseumnida
I'll do it. (volunteering — the will-flavored -겠)
주말에는 아무것도 안 할 거예요.
jumareneun amugeotdo an hal geoyeyo
I'm not going to do anything this weekend. (a plan — 할 거예요)
The progressive: -고 있다, and its honorific 계세요
-고 있다 marks an action in progress ("is doing"). Because it ends in 있다, raising the subject swaps 있다 for its honorific counterpart 계시다 → 하고 계세요 ("[an honored person] is doing"). Do not honorifically inflect 있다 as ×있으세요 here; use 계세요.
지금 뭐 하고 있어요?
jigeum mwo hago isseoyo
What are you doing right now? (progressive — 하고 있어요)
아버지는 지금 운동하고 계세요.
abeojineun jigeum undonghago gyeseyo
My father is exercising right now. (honorific progressive — 하고 계세요)
Supplementary rows: imperative and propositive
| Mood | 합니다체 | 해요체 | 반말 | 한다체 |
|---|---|---|---|---|
| Imperative | 하십시오 (hasipsio) | 하세요 (haseyo) | 해 (hae) | 해라 (haera) |
| Propositive | 합시다 (hapsida) | 해요 (haeyo) | 하자 (haja) | 하자 (haja) |
The 반말 imperative and statement collapse to the same word — 해 is both "do it" and "(I) do." Only context and intonation separate them. (For the -시- honorific request 하세요/하십시오 and the caveats on -(으)ㅂ시다, see imperative & propositive across levels.)
그건 내가 알아서 할게. 너무 걱정하지 마.
geugeon naega araseo halge. neomu geokjeonghaji ma
I'll handle that myself, so don't worry too much. (반말 — promise 할게 + prohibition)
Connectives, attributives, and nominal forms
These clause-linkers and modifiers are what you actually string 하다 into. The -아/어 connectives take 해; the rest attach to 하-.
- Connectives: 하고 ("and, and then"), 해서 ("do and so / because"), 하면 ("if one does"), 하니까 ("since / on doing"), 하지만 ("but"). Only 해서 uses the 해 contraction; the others glue to 하-.
- Attributive (noun-modifying): 하는 (present, "that does"), 한 (past, "that did"), 할 (prospective, "to do / that will do"), 하던 (retrospective, "that used to do"). See attributive forms.
- Nominal: 하기 (the "-ing / to do" nominalizer) and 함 (the terser, more written -음 nominalizer).
열심히 준비해서 시험을 잘 봤어요.
yeolsimhi junbihaeseo siheomeul jal bwasseoyo
I prepared hard, so I did well on the exam. (준비하다 → 준비해서)
저는 요리하기를 좋아해요.
jeoneun yorihagireul joahaeyo
I like cooking. (nominal 하기; and 좋아하다 is itself a 하다-verb)
The payoff: every 하다-compound is already conjugated
This is why the page carries such weight. Chop 하다 off any compound, and the rest of the word slots into the grid untouched. 공부하다 → 공부해요, 공부했어요, 공부할 거예요, 공부하고 있어요, 공부하세요. So do 운동하다, 시작하다, 전화하다, 청소하다, 준비하다, 사랑하다, 걱정하다 — several thousand roots that plug into 하다. There is nothing else in the language with anything close to this return on one memorized paradigm.
그녀는 매일 아침 요가를 한다.
geunyeoneun maeil achim yogareul handa
She does yoga every morning. (한다체 present — 한다)
Common Mistakes
1. Regularizing the past as ×하았어요. 하 + 였 contracts to 했, always — never ×하았- or ×하였- in speech.
❌ 어제 대청소하았어요.
Wrong — 하 + 였 → 했; it's 대청소했어요.
✅ 어제 대청소했어요.
eoje daecheongsohaesseoyo
I did a big clean-up yesterday.
2. Attaching 요 to the bare stem (×하요). The present is 해요, built on the 해 contraction, not 하 + 요.
❌ 저는 요리를 자주 하요.
Wrong — the present of 하다 is 해요, not ×하요.
✅ 저는 요리를 자주 해요.
jeoneun yorireul jaju haeyo
I cook often.
3. Spelling the future as ×할 거에요. After the vowel-final 거, the copula is 예요 — 할 거예요, never ×거에요.
❌ 내일 뭐 할 거에요?
Wrong spelling — after a vowel it's 예요: 할 거예요.
✅ 내일 뭐 할 거예요?
naeil mwo hal geoyeyo
What are you going to do tomorrow?
4. Honorific progressive as ×하고 있으세요. Raise the subject by swapping 있다 → 계시다: 하고 계세요.
❌ 사장님은 회의를 하고 있으세요.
Wrong — the honorific of 있다 here is 계시다: 하고 계세요.
✅ 사장님은 회의를 하고 계세요.
sajangnimeun hoeuireul hago gyeseyo
The boss is in a meeting. (honorific progressive)
5. Leaving 하여 uncontracted in speech. 하여요 / 사랑하여 are archaic; modern Korean fuses them to 해요 / 사랑해.
❌ 나 너 정말 사랑하여.
Archaic/literary — say 사랑해.
✅ 나 너 정말 사랑해.
na neo jeongmal saranghae
I really love you.
Key Takeaways
- Every -아/어 cell of 하다 is 해 (하 + 여 → 해): 해요, 해, 했어요, 했습니다, 해서, 해야. Never derive ×하아/×하어.
- -겠 and -고 있다 attach to the bare 하-: 하겠어요, 하고 있어요 (honorific 하고 계세요).
- 한다체 present is 한다 — the one non-해 cell.
- Future splits: -겠 = will/intention + formal; 할 거예요 = plan/prediction (spell 거예요).
- The whole grid propagates to every noun+하다 verb — 공부하다, 운동하다, 사랑하다 — which is why this is the highest-leverage paradigm in Korean.
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Start learning Korean→Related Topics
- 공부하다 (to study): 하다-Verb ParadigmTOPIK 1 — The full look-up paradigm of a noun+하다 verb, built on 공부하다 (stem 공부하-) — the single most productive verb pattern in Korean. Master this one grid and you conjugate thousands of 하다-verbs by swapping the noun.
- The Vowel-Contraction TableTOPIK 1 — The obligatory stem-vowel + 아/어 fusions that produce every 해요체 and past form — 가+아→가, 오+아→와, 주+어→줘, 마시+어→마셔 — plus the 되/돼 spelling test. The uncontracted forms are simply wrong.
- Progressive & Resultant State: -고 있다 vs -아/어 있다TOPIK 2 — English '-ing' is ambiguous between an action underway and the state it leaves behind; Korean forces the choice. -고 있다 marks an action in progress (먹고 있어요 'is eating'); -아/어 있다 marks a resultant state that persists after a change is complete (앉아 있어요 'is seated'). This table draws the line, verb by verb.
- 하다 → 해: The 여-ContractionTOPIK 1 — The one lexical exception to vowel harmony: 하다 takes neither -아 nor -어 but the archaic allomorph -여, and 하 + 여 always contracts to 해 — a single fixed output that conjugates thousands of 하다-compounds (공부해요, 사랑해, 시작해서).
- 하다 Verbs: The Most Productive Engine in KoreanTOPIK 1 — 하다 ('to do') attaches to a noun to build a verb or adjective — 공부하다, 일하다, 조용하다 — splitting into action verbs and descriptive verbs; it has one memorized conjugation (하 + 여 → 해) that thousands of words inherit.