이/가

Used to mark the subject of a sentence in Korean. This particle indicates who or what is performing the action or being described.

We have a lesson explaining the difference between the subject and topic marker.
You can read it here.

Conjugation

All Tenses
N (V) 딸기 딸기가
N (C) 수박 수박이

Changes

When used with certain words the form changes.

Example Sentences

Polite

학생이 공부해요.
The student studies.

Polite

책이 비싸요.
The book is expensive.