것 as Nominalizer: -는 / -(으)ㄴ / -(으)ㄹ 것

You already know 것 as the everyday noun "thing / one" — 이거 ("this one"), 내 거 ("mine"), 빨간 거 ("the red one"). This page is about 것's biggest job of all: turning an entire clause into a noun. Put a whole sentence in front of 것 (in its modifier form) and 것 packages it up as a single noun phrase — "the fact that…," "the act of…," "the thing that…" — which can then take a particle and serve as a subject or object.

This is what lets Korean say things English says with -ing gerunds and that-clauses. "Learning Korean is fun," "I didn't know that he'd left," "there's nothing to eat" — all three are built in Korean with [clause] + 것. Master this and you unlock a huge amount of natural, connected speech.

The mechanism: modifier + 것 + particle

Korean has no relative pronoun like that or which. Instead, a clause modifies a noun by putting the verb into a modifier (attributive) ending and placing the noun right after it — the whole clause leans forward onto that noun. When the noun is the semantically empty 것, the result is a nominalized clause: the clause becomes the noun.

Look at the architecture: 한국어를 배우다 ("to learn Korean") → put 배우다 into its present modifier form 배우는 → add 것 → now 한국어를 배우는 것 is a noun phrase, "the learning-of-Korean," and it takes the subject particle 이 (heard as 게 in speech) to become the subject of 재미있어요. The clause has been boxed into a noun.

Tense lives in the modifier, never on 것

This is the single most important rule on the page, and the one learners break most. 것 itself never changes for tense. All the tense information sits in the modifier ending on the verb. There are three, and switching between them is how you move the clause through time:

Same 것 in all three rows. The contrast — present, past, future — is entirely in the ending 먹는 / 먹은 / 먹을. Here is each one at work:

The allomorphy of the past modifier

The past modifier -(으)ㄴ splits by the verb stem: after a consonant (batchim) it's -은, after a vowel it's just -ㄴ, and a ㄹ-final stem drops its ㄹ before it.

In speech: 것 → 거, and the particle fuses

Just as with the general noun, clause-nominalizing 것 almost always contracts to 거 in conversation, and the following particle fuses with it: 것이 → 게, 것은 → 건, 것을 → 걸, 것이에요 → 거예요. Learn these as single units — natural speech uses them by default.

What 것 adds: a huge family of patterns

Because 것 nominalizes anything, it feeds a whole set of high-frequency constructions you'll meet again and again. A few you can start using now:

• -는 게 좋다 — "it's good to / you'd better": 일찍 자는 게 좋아요.
• -는 것 같다 — "it seems / looks like": the softening pattern behind most Korean guesses (see 것 같다).
• -(으)ㄴ 것을 알다 / 모르다 — "know / not know that…": for reporting facts.

것 vs. -기 vs. -(으)ㅁ: three nominalizers

것 is not Korean's only way to nominalize — it is one of three, and each has a niche. 것 is the concrete one: a fact, an act, or a thing you could point to. -기 names an activity and is what you use after verbs like 좋아하다, 싫어하다, 시작하다 and in list-like labels (수영하기 "swimming," 읽기 "reading"). -(으)ㅁ is the abstract, formal nominalizer, common in writing and dictionary-style notes (죽음 "death," 있음 "existence").

Roughly: if you can replace it with English "the fact/act/thing that…," use 것; if it's a bare activity name (a hobby, a skill), -기 often fits better; if it's abstract and formal, -(으)ㅁ. The full comparison lives on its own page — see 기 vs. 음 vs. 것.

Common Mistakes

1. Putting the tense on the wrong place — present modifier where the past belongs. The clause's time is set by the modifier ending. For "the thing I bought," the verb must be past-modified 산, not present 사는.

• ✗ 어제 사는 것이 고장 났어요.
• ✓ 어제 산 것이 고장 났어요. — "The thing I bought yesterday broke."

2. Wrong allomorph on the past modifier. After a vowel stem it's -ㄴ (not -은), and a ㄹ-stem drops its ㄹ.

• ✗ 가은 것 / ✗ 만들은 것
• ✓ 간 것 / ✓ 만든 것

3. Reaching for -기 where a fact needs 것. Complements of "know / not know / realize" report a fact, and facts take 것, not -기.

• ✗ 그가 떠나기를 몰랐어요.
• ✓ 그가 떠난 것을 몰랐어요. — "I didn't know he'd left."

4. Marking tense twice — once on the modifier and again on the copula. Say the tense once, on the modifier. For "this is something I made," the past sits in 만든; the copula stays present.

• ✗ 이건 제가 만든 것이었어요. (now it reads "this was something I had made")
• ✓ 이건 제가 만든 거예요. — "This is something I made."

5. Gluing 것 to the verb with no space. 것 is a bound noun but still a separate word: write a space after the modifier.

• ✗ 먹는것이 / ✗ 할걸
• ✓ 먹는 것이 / ✓ 할 걸

Key Takeaways

• 것 nominalizes a whole clause: [clause + modifier ending] + 것 becomes a noun phrase that can take a particle.
• Tense lives in the modifier, never on 것: 먹는 것 (present) / 먹은 것 (past) / 먹을 것 (prospective).
• Past modifier allomorphy: consonant → -은 (먹은), vowel → -ㄴ (간), ㄹ-stem → drop ㄹ (만든).
• In speech 것 → 거, and the particle fuses: 것이 → 게, 것은 → 건, 것을 → 걸, 것이에요 → 거예요.
• 것 is the concrete nominalizer (fact / act / thing); -기 names an activity, -(으)ㅁ is abstract / formal.