TOPIK II · Level 3

-(으)ㄴ/는지 알다/모르다

know or not know whether, what, when

Embeds a question inside a sentence. Korean leaves the question word exactly where it stood — no reordering, no extra word for “whether.”

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    +-(으)ㄴ/는지 알다

    stemending

    When to use it

    The form follows the modifier system: verbs take -는지, adjectives -(으)ㄴ지, and the past is -았/었는지 for everything. For something not yet decided, -(으)ㄹ지. Stems in ㄹ drop it: 아는지, 만드는지.

    It works with or without a question word. 언제 오는지 알아요? asks when; 오는지 알아요? asks whether. The structure does not change.

    Note the particle: what you know is marked with 을/를 when the embedded clause is treated as an object, but in practice Korean simply says 언제 오는지 알아요 with no particle at all — and that is the natural form.

    모르다 is used far more than 알다 here, because saying you do not know is the more common conversational move: 어디에 있는지 모르겠어요.

    How to attach it

    Word typeFormExample
    Verb, present-는지오다 → 는지
    Adjective-(으)ㄴ지좋다 → 은지
    Past, any word type-았/었는지는지
    Not yet decided-(으)ㄹ지 모르겠어요
    Ends in ㄹㄹ drops알다 → 아는
    이다-인지학생인지

    In use

    1. 그 사람이 언제 오는지 알아요?

      Do you know when he’s coming?

    2. 화장실이 어디에 있는지 모르겠어요.

      I don’t know where the toilet is.

    3. 이 음식이 매운지 좀 알려 주세요.

      Please let me know whether this dish is spicy.

    4. 어제 무슨 일이 있었는지 아세요?

      Do you know what happened yesterday?

    5. 내일 갈지 안 갈지 아직 모르겠어요.

      I still don’t know whether I’ll go tomorrow or not.

    6. 그분이 한국 사람인지 물어봤어요.

      I asked whether he was Korean.

    Compared with

    • -(으)냐고 하다

      -냐고 reports a question someone asked; -는지 embeds a question inside knowing, wondering, or checking. Both translate as “whether.”

      오냐고 물었어요. (he asked whether I’m coming)  /  오는지 몰라요. (I don’t know whether he’s coming)

    • -(으)ㄴ 지

      A different word that looks nearly identical. -(으)ㄴ 지 with a space measures elapsed time; -는지 joined means “whether.”

      온 지 3년 됐어요. (three years since coming)  /  오는지 몰라요. (whether he’s coming)

    • -(으)ㄹ지

      Used when the matter is undecided or lies ahead. 갈지 모르겠어요 is about a decision not yet made; 가는지 모르겠어요 is about a fact you lack.

      갈지 모르겠어요. (I haven’t decided)  /  가는지 모르겠어요. (I don’t know if he goes)

    Watch out

    • 이 음식이 맵는지 알려 주세요.

      이 음식이 매운지 알려 주세요.

      맵다 is an adjective, so it takes -(으)ㄴ지. -는지 belongs to verbs and the 있다 group.

    • 그 사람이 뭘 만들는지 모르겠어요.

      그 사람이 뭘 만드는지 모르겠어요.

      Stems ending in ㄹ drop it before -는지, as everywhere in the modifier system.

    • 그 사람이 언제 오는 지 알아요?

      그 사람이 언제 오는지 알아요?

      Written joined it means “whether.” With a space it becomes the unrelated -(으)ㄴ 지 that measures elapsed time.

    Next

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