Object Particles

을/를: the object particle, and where it hides

Picking the right one

The mechanical rule is the easy half, and it's the same shape as every other Korean particle pair.

• 을 after a noun ending in a consonant: 책을 (chaeg-eul), "book"
• 를 after a noun ending in a vowel: 영화를 (yeonghwa-reul), "movie"

That's it. The particle marks the thing the verb happens to.

The difference between 를 and 은 in Korean

Once the object particle itself makes sense, this is the pair that starts causing trouble. Both can follow the same noun, and English shows no difference at all, but they are doing separate jobs.

를 marks the thing the verb acts on. 은 marks what the sentence is about, and usually hints at a contrast.

• 책을 읽어요. (chaeg-eul ilgeoyo) — "I read a book." 을 points at what gets read.
• 책은 읽어요. (chaeg-eun ilgeoyo) — "The book, I do read." 은 sets the book up as the topic, and quietly suggests there's something else you don't read.

So 을/를 answers "what did the verb happen to", and 은/는 answers "what are we talking about".

Verbs that take an object when English doesn't

A handful of Korean verbs mark their target with 을/를 where English reaches for a preposition. These are worth memorizing as pairs, because translating word by word produces something wrong.

• 친구를 만나요. (chingu-reul mannayo) — "I meet a friend." Not "meet with".
• 버스를 타요. (beoseu-reul tayo) — "I take the bus."
• 학교를 다녀요. (hakgyo-reul danyeoyo) — "I attend school."

Movement verbs do something similar with paths and places:

• 길을 걸어요. (gir-eul georeoyo) — "I walk along the street."
• 다리를 건너요. (dari-reul geonneoyo) — "I cross the bridge."

The street isn't being acted on the way a book is, but Korean treats the path as the object anyway.

It disappears in speech

In casual conversation the object particle drops constantly, because the verb usually makes the roles obvious.

• 밥 먹었어? (bap meogeosseo?) — "Did you eat?" Nobody says 밥을 먹었어 among friends.

It comes back the moment there's any risk of confusion, or when you want to lean on the object specifically. There's a whole post about when particles vanish if that habit interests you.

And it gets replaced

을/를 doesn't stack with 도 or 만. Those take its place:

• 책을 + 도 → 책도 (chaek-do), "the book too". Never 책을도.
• 책을 + 만 → 책만 (chaek-man), "only the book". Never 책을만.