Korean Question Words: 뭐, 누구, 어디, 언제, 왜, 어떻게
Korean has six core question words — 뭐 (what), 누구/누가 (who), 어디 (where), 언제 (when), 왜 (why), and 어떻게 (how) — and none of them flip the sentence around. You keep normal word order and just drop the question word into its slot, then lift your pitch at the end: 이거 뭐예요? (literally 'this what is?') means 'What is this?'.
English makes you rebuild the whole sentence to ask a question. "You are tired" becomes "Are you tired?" — the verb jumps to the front, and if there's no auxiliary verb you have to invent one ("you like it" → "do you like it?"). Korean skips all of that. You say the sentence in the exact same order you'd use to answer it, slot in a question word, and raise your voice at the end. That's the whole system.
This is the shortest grammar lesson in the language and one of the highest-leverage ones — six words unlock most of what you'll actually say in a conversation, from "what happened" texts to a drama character snapping "누가 그랬어" (who did that) mid-argument.
The six question words — and the two that aren't quite what they look like
Four of these behave exactly like you'd expect. Two of them hide a small trap that trips up almost everyone in month one.
| Word | Romanization | Meaning | Note |
|---|---|---|---|
| 뭐 | mwo | what (spoken) | a contraction of 무엇 — this is the one you'll actually say |
| 무엇 | mu-eot | what (formal/written) | news anchors and forms: 성함이 무엇입니까? (what is your name) |
| 누구 | nu-gu | who (base form) | used with particles: 누구랑 (with whom), 누구한테 (to whom) |
| 누가 | nu-ga | who (subject form) | = 누구 + 가, always contracted — nobody says 누구가 |
| 어디 | eo-di | where | 어디예요? / 어디 가요? |
| 언제 | eon-je | when | no separate future or past form — context carries the tense |
| 왜 | wae | why | also stands alone as a full sentence, see the drama section below |
| 어떻게 | eo-tteo-ke | how | an adverb — do not confuse it with 어때요, see below |
The 뭐/무엇 split is a register thing, not a meaning thing: 뭐 is what you'll hear and say roughly 95% of the time, 무엇 is what shows up in job interviews and TV news. The 누구/누가 split is different — it's not politeness, it's grammar. 누구 is the word "who"; 누가 is what happens when "who" becomes the subject of the sentence and the subject marker 가 fuses onto it. You could technically write 누구가, but no Korean speaker ever does. It's always 누가.
No inversion, no auxiliary verbs — just point and raise your voice
This is the part that makes Korean questions genuinely easier than English ones, and textbooks tend to bury the lede on it. There's no "do/does/did" to insert, no verb to move, no word order to relearn. The question word sits in the same spot the answer would go, and a rising intonation at the very end is what tells the listener "this is a question, please respond."
이거 뭐예요?
i-geo mwo-ye-yo?
What is this?
literally "this what is" — nothing moves
언제 가요?
eon-je ga-yo?
When are you going?
same slot the time word 내일 (tomorrow) would go in
왜 그래요?
wae geu-rae-yo?
Why are you like that? / What's wrong?
the go-to line when a friend looks upset
누가 그랬어요?
nu-ga geu-rae-sseo-yo?
Who did that?
누가 fills the subject slot, exactly where a name would go
This also means you can turn almost any statement into a question by mentally replacing one piece of it. "저는 학생이에요" (I'm a student) → replace 학생 with 뭐 and flip the particle → "뭐예요?" You're not learning new grammar here, just new vocabulary slotted into grammar you already have.
몇 vs 얼마나: counting things vs measuring things
These two get taught as synonyms and they aren't. 몇 (myeot) asks for a number and always wants a counter word stapled to it — it can't stand alone the way "how many" can in English. 얼마나 (eol-ma-na) asks about degree, duration, or amount, and it never takes a counter.
| Phrase | Romanization | Used for |
|---|---|---|
| 몇 개 | myeot gae | how many (general objects) — 사과 몇 개? "how many apples?" |
| 몇 명 | myeot myeong | how many (people) |
| 몇 시 | myeot si | what hour — 지금 몇 시예요? "what time is it?" |
| 몇 살 | myeot sal | how old — casual, ask peers or kids, not elders |
| 얼마 | eol-ma | how much (price, standalone) — 이거 얼마예요? "how much is this?" |
| 얼마나 | eol-ma-na | how much/long (duration, degree) — 얼마나 걸려요? "how long does it take?" |
The drama drill: 뭐, 왜, and 누구 as full sentences on their own
Here's the part that actually makes you sound native instead of textbook-native: Koreans drop question words in as standalone reactions constantly. "뭐?" by itself means "what?" the way you'd blurt it out. "왜?" alone — especially clipped and flat — is the classic curt phone-answer energy you hear right before a drama argument kicks off. Add pitch and 요 and it turns warm; drop both and it turns sharp. Same word, opposite mood, entirely carried by tone.
저 다음 주에 일본 가요.
jeo da-eum ju-e il-bon ga-yo.
I'm going to Japan next week.
뭐??
mwo??
What??
일 때문에요. 화보 촬영이요.
il ttae-mu-ne-yo. hwa-bo chwa-ryeong-i-yo.
It's for work. A photo shoot.
왜 이제 말해요?!
wae i-je mal-hae-yo?!
Why are you only telling me now?!
미안해요... 누구한테도 아직 말 안 했어요.
mi-an-hae-yo... nu-gu-han-te-do a-jik mal an hae-sseo-yo.
Sorry... I haven't told anyone else yet.
Two mix-ups that give away a beginner
어떻게 vs 어때요
어떻게 is an adverb — it modifies a verb, as in 어떻게 가요? ("how do I get there," literally "how [do you] go"). 어때요 is a completely different word, a full predicate meaning "how is it / what do you think," as in 이 노래 어때요? ("how's this song / what do you think of this song"). Textbooks list 어떻게 as "how" and stop, so learners try to force it into asking someone's opinion and produce broken sentences like 이거 어떻게? when they mean 이거 어때요? They are not interchangeable, and mixing them up is the single most common tell that someone learned Korean from a word list instead of a conversation.
왜 without any softening
On a flashcard, 왜 just means "why." In real speech, a flat unfriendly "왜" — no rising pitch, no 요 — reads as "WHAT do you want," the tone of someone who did not want to be interrupted. If you're asking a genuine question, let your pitch rise and keep the 요: 왜요? sounds curious. 왜. said flat sounds like you're bracing for an argument.
Once these six words and their traps are automatic, the rest of Korean questions is just particle work layered on top — the question words themselves never change.
Frequently asked questions
What is "what" in Korean?
뭐 (mwo) is the word you'll actually use — it's the spoken contraction of 무엇, which shows up mainly in formal or written Korean. 이게 뭐예요? ("what is this?") is the everyday version; 무엇입니까? is the formal-interview version of the same question.
Why is it 누가 instead of 누구가?
누구 means "who," and 가 is the subject-marking particle. When "who" is the subject of a sentence, 누구 and 가 always contract into 누가 — this is one of the few particle contractions in Korean that has zero exceptions, so 누구가 will just sound wrong to any native speaker.
Does Korean change word order to ask a question?
No. Korean keeps the same subject-object-verb order for statements and questions — you insert the question word into the slot the answer would occupy and raise your pitch at the end. There's no equivalent of English's "do/does" insertion or subject-verb inversion.
What's the difference between 몇 and 얼마나?
몇 (myeot) asks for a countable number and needs a counter word attached — 몇 개, 몇 명, 몇 시. 얼마나 (eol-ma-na) asks about degree, duration, or amount without any counter, as in 얼마나 걸려요? ("how long does it take?"). 얼마 alone asks specifically about price.
Is 어떻게 the same as 어때요?
No, and mixing them up is a common beginner error. 어떻게 is an adverb meaning "how," used before a verb: 어떻게 가요? ("how do I get there?"). 어때요 is a standalone predicate meaning "how is it / what do you think": 이거 어때요? ("how's this?"). They aren't swappable.