Korean Particle 이/가: Subject Marker

Marks the grammatical subject. Use 이 after consonant, 가 after vowel.

The Rule

Marks the grammatical subject. Use 이 after consonant, 가 after vowel. Particles are the backbone of Korean grammar. Unlike English, which relies on word order to show who does what, Korean uses small markers attached directly to nouns. 이/가 is one of the most fundamental particles you'll encounter, and understanding it correctly will dramatically improve your Korean comprehension.

Why English Speakers Get It Wrong

English doesn't have particles like 이/가. In English, word order and prepositions do the job — "I gave the book to him" uses position and "to" to clarify meaning. Korean particles attach directly to nouns and change the grammatical role, which feels alien at first. The biggest confusion comes from trying to translate particles one-to-one with English prepositions. 이/가 doesn't map neatly to any single English word. Instead, think of it as a grammatical tag that tells you the noun's role in the sentence.

How It Works

Marks the grammatical subject. Use 이 after consonant, 가 after vowel. 이/가 attaches directly after a noun with no space. If the noun ends in a consonant (받침), the form may change — this is called "받침 sensitivity" and it's a pattern you'll see across Korean grammar. Pay attention to how native speakers use 이/가 in real conversations. You'll start noticing patterns quickly.

Real Examples

• 비가 와요. (biga wayo.) — "Rain is coming. (It's raining.)" [비 ends in vowel → 가] • 물이 필요해요. (muri piryohaeyo.) — "I need water." [물 ends in ㄹ → 이] • 누가 왔어요? (nuga wateoyo?) — "Who came?" [누구 + 가 → 누가 (contraction)]

Common Mistakes

❌ 비는 와요. (bineun wayo.) ✅ 비가 와요. (biga wayo.) → For weather/nature events introducing new info, use 이/가 (subject), not 은/는 (topic).

Quick Tip

Practice by labeling objects around you with 이/가. Say the noun + particle out loud until it feels natural. When reading Korean, circle every 이/가 you see and ask yourself WHY it was used there — this active reading habit builds intuition faster than memorizing rules.

Remember: Marks the grammatical subject. Use 이 after consonant, 가 after vowel.

Examples

비가 와요. — biga wayo. — Rain is coming. (It's raining.)

물이 필요해요. — muri piryohaeyo. — I need water.

누가 왔어요? — nuga wateoyo? — Who came?