How to Say “I Don't Understand” in Korean (and What to Say Next)

"I don't understand" in Korean splits in two: 이해가 안 돼요 (ihaega an dwaeyo) for a concept or explanation that doesn't make sense, and 못 알아들었어요 (mot aradeureosseoyo) for speech you physically couldn't catch — wrong verb, wrong sympathy. Pair either with 다시 말씀해 주세요 (say it again) or 천천히 말해 주세요 (slower, please) and most Koreans will happily reset for you.

Textbooks teach one "I don't understand" and call it a day. Real conversations need two, because "I don't get this rule" and "I couldn't hear what you just said" are completely different problems — and Korean, unhelpfully specific about everything else, actually has a word for each.

Mix them up and you're not wrong exactly, just slightly off — like answering "what did you say?" with "I don't follow your logic." Below: which is which, the three phrases that get you an actual redo, and the one habit that quietly wrecks more beginner conversations than any grammar mistake.

Two different "I don't understand"s

Here's the tell: 이해가 안 돼요 works even if someone whispered a perfectly clear sentence you just don't grasp — say, someone explaining Korean age math for the third time. 못 알아들었어요 works even if the sentence was trivially simple, if it flew by too fast to register. A Korean friend saying "오늘 저녁에 뭐 먹을래?" too quickly gets 못 알아들었어요, not 이해가 안 돼요 — there was nothing to understand, you just didn't hear it.

The survival trio: what to say right after

"I don't understand" on its own is a dead end — it tells someone there's a problem but not what to do about it. Pair it with one of these three and the conversation actually moves forward.

뭐라고요? is doing the most cultural work of the three. It's short enough to fire off mid-conversation without breaking the flow, and Koreans use it constantly with each other — it's not a beginner crutch, it's just how people ask. Drop the -요 for 뭐라고 with close friends; keep it with anyone older, a cashier, or a stranger.

한국어 잘 못해요: the phrase that buys you patience

"저 한국어 잘 못해요" (jeo han-gu-geo jal mot-hae-yo — "I don't speak Korean well") sounds like a confession of failure in English. In Korean, it's closer to a magic word. Say it early in a conversation with a stranger — a cashier, a taxi driver, someone giving you directions — and the whole exchange changes shape: shorter sentences, more patience, sometimes an actual smile.

Part of this is cultural. Koreans generally read a foreigner attempting Korean at all as effort worth rewarding, and naming your own limit up front removes the awkward guessing game of "does this person understand me or are they just nodding." It also gives you permission — once you've said it, asking someone to repeat themselves twice in a row doesn't feel like you're being difficult. You already told them the deal.

The 네네 trap

Every beginner does this at least once: someone says something you half-catch, and instead of asking again, you say "네네" (ne-ne — "yes yes") and hope context fills the rest in. Sometimes it works. Often it doesn't, and you end up agreeing to a meeting time you didn't hear, or nodding along to a joke you missed the setup of.

The 네네 reflex comes from a real fear — that asking again marks you as the person who can't keep up. It's backwards. Koreans ask each other 뭐라고요? and 다시 말해 줄래? constantly, in Korean, with no foreign-language excuse at all — background noise and fast talkers don't care about your fluency level. Nobody's tracking how many times you ask. They're tracking whether the plan actually got made.

This is also the exact reflex story-based practice is good at unlearning — a DM conversation that keeps going lets you actually ask "뭐라고요?" and see the reply, instead of freezing a textbook dialogue mid-sentence.