은/는 vs 이/가: When to Use Each Korean Particle
The clear guide to Korean topic and subject particles. 은/는 says what you are talking about, 이/가 points at who or what. Six rules, tappable examples and a quick quiz.
Beginner8 min readTap any Korean word to see it explained
The short answer
은/는 marks the topic: what you are talking about, like “as for X.” 이/가 marks the subject and puts the spotlight on it: new information, the answer to “who?” or “what?”, or the thing that exists, is liked or is described.
Pick the form by the last sound of the noun: 은 / 이 after a consonant, 는 / 가 after a vowel.
These two pairs are the first thing that trips up almost every Korean learner, because English has nothing quite like them. The good news: six patterns cover nearly every sentence you will meet. Tap any word in the examples below to see what it means and save it to your flashcards.
Which form: 은 or 는, 이 or 가?
This part is pure sound. Look at the last letter block of the noun: does it end in a consonant (a 받침), or a vowel?
| Noun ends in | Topic | Subject | Examples |
|---|---|---|---|
| a consonant | 은 | 이 | 책은, 책이 · 선생님은, 선생님이 |
| a vowel | 는 | 가 | 커피는, 커피가 · 친구는, 친구가 |
A few short words change shape before 가: 저 → 제가, 나 → 내가, 너 → 네가, and 누구 → 누가. You will hear 네가 pronounced 니가 in songs and dramas, so it doesn’t sound like 내가.
1. 은/는 sets the topic
Use 은/는 to say what the sentence is about. Introducing yourself is the classic case: the topic is you, and the rest of the sentence tells us something about you.
2. 이/가 answers “who?” and “what?”
When the subject is the new or important part of the sentence, use 이/가. Question words like 누가 (who) and 뭐가 (what) always take it, and so does the answer.
민수는 왔어요 would sound like "Minsu came (but someone else didn't)", which is rule 3.
3. 은/는 compares and contrasts
Put 은/는 on two things and you are setting them against each other, like stressing a word in English: “Coffee I like. Tea, not so much.”
4. 이/가 for what exists, is liked or is described
With 있다 (to have, to exist), 없다 (to not have), and describing words like 좋다 (to be good), the thing that exists or is described takes 이/가. This is how both particles end up in one sentence: the person is the topic, the thing is the subject.
Literally "as for me, you are good." This is why 좋다 takes 이/가 on the thing you like.
5. 이/가 with “not be” and “become”
아니다 (to not be) and 되다 (to become) take 이/가 on the thing you are not, or are becoming. It looks like a second subject, and that is normal.
6. Inside a describing phrase, always 이/가
When a whole phrase describes a noun (“the song I like”, “the day we met”), the subject inside that phrase takes 이/가. 은/는 belongs to the sentence as a whole, so it can’t sit inside the phrase.
Careful: the 는 in 좋아하는 is a verb ending meaning "that ...", not the topic particle.
Three mistakes to stop making
- 누구는 왔어요? Question words take 이/가: 누가 왔어요?
- 저가 is never right. Before 가 it is 제가.
- 저는 좋아하는 노래 breaks rule 6. Say 제가 좋아하는 노래.
Hear it in songs
Once you know the six rules, you will notice 나는, 내가 and 네가 in almost every K-pop chorus. Open any song in Hanbok Lyrics, tap a line, and the breakdown marks each particle for you.
Check yourself
Quick check · 1 of 5책 + topic particle = ?
책 ends in a consonant (ㄱ).
Questions learners ask
What is the difference between 은/는 and 이/가?
은/는 marks the topic: what the sentence is about, often something already known or being contrasted ("as for me..."). 이/가 marks the subject, and puts the focus on it: new information, the answer to "who?" or "what?", or the thing that exists, is liked or is described.
When do I use 은 vs 는, and 이 vs 가?
It depends only on the last sound of the noun. After a consonant use 은 or 이 (책은, 책이). After a vowel use 는 or 가 (커피는, 커피가).
Why is it 제가 and not 저가?
A few short words change shape before 가: 저 becomes 제가, 나 becomes 내가, 너 becomes 네가, and 누구 becomes 누가.
Can Korean speakers leave these particles out?
Yes. In casual speech both are often dropped when the meaning is clear, as in 나 학생이야 ("I'm a student"). Learners should still know them, because they change the meaning when they are there.