Subject and Topic Markers 이/가 and 은/는

In Korean, small words called particles or markers attach to nouns to show their grammatical role in a sentence. This is different from English, which uses word order (like Subject-Verb-Object) to show these roles.

The two most fundamental markers are 이/가 and 은/는 .

이/가 is the subject marker . It typically points out who or what is performing an action or being described.

은/는 is the topic marker . It sets the general topic of the sentence—what you're talking about . It's also frequently used to show contrast.

Understanding the difference between these two is a key step to making natural-sounding Korean sentences.

The specific form you use depends on whether the preceding noun ends in a consonant (받침) or a vowel.

Ends in... · Subject Marker · Topic Marker

Consonant · 이 (e.g., 책 + 이 → 책이 ) · 은 (e.g., 학생 + 은 → 학생은 )

Vowel · 가 (e.g., 고양이 + 가 → 고양이가 ) · 는 (e.g., 저 + 는 → 저는 )

This rule is very consistent, so it's important to memorize it.

The subject marker 이/가 identifies the specific subject of a predicate (a verb or adjective). Think of it as putting a spotlight on the doer of the action or the subject of the description.

It's very common in these situations:

Introducing new information: When you mention something for the first time.

Answering "Who?" or "What?": To identify the specific person or thing responsible.

Example

Q: 누가 왔어요? ( Who came?)

A: 미나가 왔어요. ( Mina came.)

Here, Mina is the new and essential piece of information that answers the question "who," so 가 is the natural choice.

The topic marker 은/는 has two primary functions. It sets a general topic or shows contrast.