·4 min read

Korean Particles 이/가 vs 은/는: What Nobody Explains Clearly

The most common particle confusion for Korean learners — and the one practical rule that makes it finally click.

For Korean learners at beginner to intermediate level


If you've studied Korean for more than a week, you've already hit this wall.

Someone says 나는 in one sentence, then 내가 in the next — and both mean "I." Your textbook labels them "topic marker" and "subject marker" and moves on. Not helpful.

Here's what's actually going on.


The Short Answer

은/는 marks what you're talking about (the topic). 이/가 marks who or what does the action (the subject — often new information).

That's the rule. The nuance is in how you apply it.


The Practical Rule

Use 은/는 when:

  • You're introducing or switching a topic
  • You're making a general statement
  • You're implying contrast

저는 학생이에요. — I'm a student. (Topic: me)

Use 이/가 when:

  • You're identifying who does something (new info)
  • You're answering "who?" or "what?"
  • You want to emphasize the subject

누가 했어요? 제가 했어요. — Who did it? I did.


Side by Side

나는 커피를 좋아해요. — I like coffee. (Topic: me)

커피가 맛있어요. — The coffee is delicious. (Subject: the coffee is the one being delicious)

The coffee is not a topic being discussed — it's the thing being something. That's 이/가 territory.


Why This Matters for Writing

When you write a Korean diary, particle errors are the most common mistakes — subtle enough that you won't catch them yourself.

You might write 저는 갔어요 when 제가 갔어요 sounds more natural. Both are understandable, but one sounds like a native speaker and one doesn't.

That gap — between "understandable Korean" and "natural Korean" — is exactly what structured correction closes. Not just flagging errors, but explaining why one choice sounds better.


Write a Korean diary entry today and find out which particles you're getting wrong. Try Korean Diary AI →