Lesson 3Beginner

Topic 은/는 vs Subject 이/가

What it means

Both attach to nouns. 은/는 marks the topic — what the sentence is about, like "As for me, …". 이/가 marks the subject and points at new or important information, especially the answer to "who?" or "what?".

How to make it

Ends in a consonant → 은 / 이: 책 → 책은, 책이
Ends in a vowel → 는 / 가: 저 → 저는, 친구 → 친구가
Special forms: 누구 + 가 → 누가 (who), 저 + 가 → 제가 (I), 나 + 가 → 내가 (I)

When to use it

은/는 to introduce yourself or set the topic: 저는 캄보디아 사람이에요. = I am Cambodian.
은/는 for general facts: 고양이는 귀여워요. = Cats are cute.
은/는 for contrast: 사과는 좋아하지만 바나나는 안 좋아해요. = I like apples, but I don't like bananas.
이/가 to describe something new you notice: 날씨가 좋아요. = The weather is nice.
이/가 with question words like 누가 and 뭐가, and in their answers: 누가 전화했어요? — 선생님이 전화했어요. = Who called? — The teacher called.

Compare

저는 민수예요. = "I'm Minsu." (introducing yourself) vs 제가 민수예요. = "I'm the one who is Minsu." (answering "Who is Minsu?")
커피는 좋아해요. = "Coffee, I like." (suggests: but maybe not other drinks) vs 커피를 좋아해요. = "I like coffee." (a plain statement, no contrast)

Common mistakes

❌ 누구는 왔어요? → ✅ 누가 왔어요? (a question word used as the subject takes 이/가)
❌ 나가 했어요 → ✅ 내가 했어요 (나 + 가 becomes 내가; 저 + 가 becomes 제가)
❌ 책는 → ✅ 책은 (책 ends in a consonant, so 은)

💡 Tip: If you can start the English sentence with "As for …,", use 은/는. If the word is the answer to "who/what?", use 이/가.

Examples

Hover or tap a word to see its meaning · grammar

.
I am Cambodian.
💡 Introducing yourself: topic 는.
? — .
Who called? — The teacher called.
💡 New information answering 'who' takes 이/가.
.
The weather is nice.
.
I like apples, but I don't like bananas.
💡 은/는 used for contrast.

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