The 하다 / 되다 / 시키다 Triplet | Korean Grammar

A large share of the Korean verb lexicon is built the same way: take a Sino-Korean action noun and glue on a light verb. The magic is that the same noun can take three different light verbs to produce three related but distinct meanings. 하다 gives you the active ("do X"), 되다 the passive or inchoative ("be X-ed / become X"), and 시키다 the causative ("make someone do X"). Learn this three-way alternation once and you unlock active, passive, and causative for hundreds of Sino-Korean verbs at a stroke — no memorizing scattered suffixes, unlike the messy native-verb causatives and passives.

The paradigm

Noun	N하다 (active)	N되다 (passive / inchoative)	N시키다 (causative)
교육 (education)	교육하다 — educate	교육되다 — be educated	교육시키다 — have [sb] educated
발전 (development)	발전하다 — develop, progress	발전되다 — be developed	발전시키다 — develop [sth]
정지 (stopping)	정지하다 — halt	정지되다 — be stopped / suspended	정지시키다 — bring [sth] to a stop
완성 (completion)	완성하다 — complete [sth]	완성되다 — be completed	완성시키다 — get [sth] completed

The three verbs differ in valency — how many participants they need and what role each plays. Watch what happens to a single noun, 발전, as we walk down the triplet:

회사가 새 기술을 발전시켰어요.

hoesaga sae gisureul baljeonsikyeosseoyo

The company developed a new technology. (causative — 회사 is the causer, 기술 the thing developed)

그 기술이 빠르게 발전됐어요.

geu gisuri ppareuge baljeondwaesseoyo

That technology was developed rapidly. (passive — 기술 is the patient; no doer named)

요즘 기술이 정말 빠르게 발전해요.

yojeum gisuri jeongmal ppareuge baljeonhaeyo

Technology is developing really fast these days. (active-intransitive — 기술 develops by itself)

Three sentences, one noun, three grammars. 시키다 adds a causer and an object; 되다 strips the doer and foregrounds the patient; 하다 (here intransitive) has the thing do it on its own.

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The triplet is a valency dial. Turn it to 시키다 to add a causer ("X makes Y develop"), to 되다 to erase the doer ("Y gets developed"), and to 하다 for the plain action. If you can build one member, you can build all three — that is why this pattern is worth over-learning.

하다 — the active

N하다 is the workhorse active verb. With a transitive noun it takes an object; with an intransitive noun it stands alone.

건설사가 드디어 다리를 완성했어요.

geonseolsaga deudieo darireul wanseonghaesseoyo

The construction company finally completed the bridge. (transitive 완성하다 + object)

한국 경제가 빠르게 발전했어요.

hanguk gyeongjega ppareuge baljeonhaesseoyo

The Korean economy developed rapidly. (intransitive 발전하다, no object)

This transitive/intransitive split inside 하다 matters, because it decides how clean the rest of the triplet is — see the overlap note below.

되다 — the passive / inchoative

N되다 removes the doer and presents the event from the patient's side: the thing "gets X-ed" or "comes to be X." It is the neutral, colorless passive of process and result — the workhorse of formal writing, news, and official notices. Full treatment on the 되다 passive page.

새 다리가 곧 완성될 거예요.

sae dariga got wanseongdoel geoyeyo

The new bridge will be completed soon.

시스템이 갑자기 정지됐어요.

siseutemi gapjagi jeongjidwaesseoyo

The system suddenly stopped / was halted.

어제 제 계정이 정지돼서 로그인을 못 했어요.

eoje je gyejeong-i jeongjidwaeseo rogeuineul mot haesseoyo

My account got suspended yesterday, so I couldn't log in.

💡

When the subject is a person, prefer 받다 over 되다 for "be X-ed." 저는 한국에서 교육받았어요 ("I was educated in Korea") sounds natural; 교육됐어요 makes a human sound like a processed object. 되다 shines with things and abstractions (기술이 발전되다, 다리가 완성되다).

시키다 — the causative

N시키다 adds a causer: someone makes or has someone/something undergo the action. The causer is the subject; the causee takes 을/를 (or, with some verbs, a dative — see causative case-marking).

부모님이 저를 좋은 학교에서 교육시켰어요.

bumonimi jeoreul joeun hakgyoeseo gyoyuksikyeosseoyo

My parents had me educated at a good school.

관리자가 그 계정을 정지시켰어요.

gwallijaga geu gyejeong-eul jeongjisikyeosseoyo

The administrator suspended that account.

Note that 시키다 is also a full independent verb — "to order (food), to make someone do (a task)": 짜장면을 시키다 "order jajangmyeon," 일을 시키다 "make someone work." The causative suffix is that verb doing light-verb duty.

점심으로 짜장면을 시켰어요.

jeomsimeuro jjajangmyeoneul sikyeosseoyo

I ordered jajangmyeon for lunch. (시키다 as a full verb — 'order')

Honest complications

The 하다/되다 overlap. When the noun is naturally intransitive (발전, 변화, 발생), 하다 already reads inchoative — 기술이 발전한다 means "the tech develops (by itself)" — so it overlaps heavily with 발전된다. Careful writers treat 발전하다 as "progress under its own steam" and 발전되다 as "be brought to develop by something," but in everyday Korean the two are often interchangeable. This is a genuine gray zone; don't expect a razor-sharp line.

시키다 can be redundant. For a noun whose 하다 form is already transitive and causative-flavored, adding 시키다 is prescriptively redundant. The famous case is 소개: 소개하다 already means "introduce (A introduces B to C)," so 소개시키다 technically duplicates the causative sense. Yet 소개시키다 is everywhere in casual speech.

제가 친구를 소개해 줄게요.

jega chingureul sogaehae julgeyo

I'll introduce you to my friend. (standard — 소개하다 already means 'introduce')

제가 친구를 소개시켜 줄게요.

jega chingureul sogaesikyeo julgeyo

I'll introduce you to my friend. (informal — common in speech, prescriptively redundant)

Common Mistakes

1. Using 시키다 where 되다 is meant. This is the core triplet error: mixing up "make it develop" with "it got developed." If nobody is causing it, you want 되다 (or intransitive 하다), never 시키다.

❌ 기술이 빠르게 발전시켰어요.

Wrong — this says 'the tech made [something] develop'; for 'the tech was developed' use 발전됐어요.

✅ 기술이 빠르게 발전됐어요.

gisuri ppareuge baljeondwaesseoyo

The technology was developed rapidly.

2. Giving 되다 an object with 을/를. 되다 is passive/intransitive — it has no object. The patient is the subject with 이/가.

❌ 회사가 기술을 발전됐어요.

Wrong — 되다 takes no object; to keep 기술 as object use the causative 발전시켰어요.

✅ 회사가 기술을 발전시켰어요.

hoesaga gisureul baljeonsikyeosseoyo

The company developed the technology.

3. Using 되다 for a human "be educated." With people, 받다 is far more natural.

❌ 저는 한국에서 교육됐어요.

Awkward — makes a person sound like a processed object.

✅ 저는 한국에서 교육받았어요.

jeoneun hangugeseo gyoyukbadasseoyo

I was educated in Korea.

4. Adding 하다 on top of 되다 or 시키다. Pick one light verb. 발전되다 and 발전시키다 are already complete verbs — you can't stack 하다 on them.

❌ 다리가 완성돼하고 있어요.

Wrong — 되다 is already the verb; it conjugates by itself as 완성되고 있어요.

✅ 다리가 완성되고 있어요.

dariga wanseongdoego isseoyo

The bridge is being completed.

Key Takeaways

One Sino-Korean noun → three verbs: N하다 (active), N되다 (passive/inchoative), N시키다 (causative).
The triplet is a valency dial: 시키다 adds a causer, 되다 erases the doer, 하다 is the plain action.
되다 takes no object (patient = subject with 이/가); 시키다 adds a causer (causee with 을/를).
With human subjects, prefer 받다 over 되다 for "be X-ed."
Two honest gray zones: intransitive 하다 overlaps with 되다 (발전하다 ≈ 발전되다), and 시키다 is redundant on already-transitive nouns (소개시키다).

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