Subject marker particles 이/가 — identifying the subject or presenting new information
Can use 이/가 to mark the subject and present new information in a sentence
Look at these examples. Can you spot the grammar pattern?
비가 와요.
It's raining.
누가 했어요?
Who did it?
고양이가 있어요.
There is a cat.
제가 할게요.
I will do it.
Pay attention to the highlighted parts. What do they have in common?
The subject markers 이 and 가 identify the grammatical subject of a sentence. They highlight new information or answer the question "who/what?"
Form:
| Condition | Marker | Example |
|---|---|---|
| After consonant (받침) | 이 | 선생님이 왔어요. (The teacher came.) |
| After vowel (no 받침) | 가 | 비가 와요. (Rain is coming.) |
When to use 이/가:
은/는 vs 이/가 side by side:
| 은/는 (Topic) | 이/가 (Subject) |
|---|---|
| 저는 학생이에요. As for me, I'm a student. | 제가 학생이에요. I (am the one who) am a student. |
| 날씨는 좋아요. The weather (in general) is nice. | 날씨가 좋아요. The weather (right now) is nice! |
Apply this grammar in A1 course exercises
Practice ExercisesUsed 이/가 where 은/는 is needed (or vice versa)
이/가 = new info, answering 'who/what?'. 은/는 = known topic, contrast. After question words → always 이/가
Used 이 after vowel or 가 after consonant
이 after 받침: 선생님이. 가 after vowel: 비가
비가 와요.
It's raining.
비 (rain) + 가 (subject): The rain IS coming — 가 presents this as new information or a current observation.
누가 했어요?
Who did it?
누구 (who) + 가 → 누가 (contracted form). Question words always take 이/가, never 은/는.
고양이가 있어요.
There is a cat.
With 있다/없다 (existence), use 이/가: 고양이 (cat) + 가 (subject) + 있어요 (exists).
제가 할게요.
I will do it.
제 (I, humble) + 가 (subject): 'I am the one who will do it.' 이/가 emphasizes the doer. Compare: 저는 할게요 (I'll do it — topic) vs 제가 할게요 (I'LL do it — I'm volunteering).
Practice in course
Apply this grammar in A1 course exercises