은/는 vs 이/가: The Ultimate Guide to Korean Topic and Subject Markers

Introduction

One of the most confusing aspects of Korean grammar for learners is understanding when to use 은/는 versus 이/가. Even advanced learners sometimes struggle with these particles. In this comprehensive guide, we'll break down the differences and help you master these essential Korean particles.

What Are 은/는 and 이/가?

은/는 - Topic Markers

• 은 is used after consonants (받침)


• 는 is used after vowels


• They mark the topic of the sentence - what you're talking about

이/가 - Subject Markers



• 이 is used after consonants (받침)


• 가 is used after vowels


• They mark the subject - who or what performs the action

Key Differences

1. New vs. Known Information

이/가 introduces new information:


고양이가 있어요. (A cat is here.) - First mention

은/는 refers to known/established topics:


고양이는 귀여워요. (The cat is cute.) - Already known

2. Contrast vs. Neutral Statement

은/는 often implies contrast:


저는 학생이에요. (As for me, I'm a student.) - Implies others might not be

이/가 makes a neutral statement:


저가 학생이에요. (I am a student.) - Simply stating a fact

3. Answering Questions

When answering "who" or "what" questions, use 이/가:


Q: 누가 했어요? (Who did it?)
A: 제가 했어요. (I did it.)

Common Mistakes to Avoid

Mistake 1: Using 은/는 for new subjects


❌ 어제 친구는 왔어요.
✅ 어제 친구가 왔어요. (A friend came yesterday.)

Mistake 2: Using 이/가 for contrast


❌ 사과가 좋아요, 바나나가 싫어요.
✅ 사과는 좋아요, 바나나는 싫어요. (I like apples, but I don't like bananas.)

Practice Examples

Korean	English	Explanation
날씨가 좋아요	The weather is good	New information
오늘 날씨는 좋아요	Today's weather is good	Contrast (implying other days aren't)
누가 학생이에요?	Who is a student?	Asking for new info
저가 학생이에요	I am a student	Answering with new info

TOPIK Tips

In TOPIK exams, pay attention to:
1. Context clues that suggest contrast (은/는)
2. Questions asking for specific information (이/가 in answers)
3. First mentions of subjects (이/가)

Conclusion

Remember these key points:


• 은/는: Topic, contrast, known information


• 이/가: Subject, new information, neutral statements

Practice regularly, and these particles will become second nature!