이/-가 in 30 Seconds
- Identifies the subject (doer) of the sentence.
- Uses '이' after consonants and '가' after vowels.
- Essential for introducing new information or specific focus.
- Changes '나' to '내', '저' to '제', and '너' to '네'.
The Korean particles 이 (i) and 가 (ga) are fundamental grammatical markers that identify the subject of a sentence. In English, the subject is usually determined by word order (the noun before the verb), but in Korean, these markers explicitly tell the listener who or what is performing the action or being described. This allows Korean word order to be much more flexible than English. While often translated as 'a/an' or 'the' depending on the context, their primary function is purely structural: they point to the 'doer' or the 'focus' of the predicate.
- Subject Definition
- The person, animal, or object that is the main focus of the verb or adjective in a specific clause.
People use 이/-가 specifically when they want to introduce new information into a conversation. If you are starting a story or pointing something out for the first time, you use these markers. For example, if you see a cat for the first time, you would say '고양이가 있어요' (There is a cat). They are also indispensable when using certain verbs like 있다 (to have/exist), 없다 (to not have/not exist), 아니다 (to not be), and 되다 (to become).
날씨가 좋아요. (The weather is good.)
Furthermore, 이/-가 provides what linguists call 'exclusive focus.' If someone asks 'Who ate the cake?', and you answer '내가 먹었어' (I ate it), the use of '가' implies that I (and not someone else) was the one who did it. This nuance is vital for clarity in Korean communication. Unlike the topic marker 은/는, which sets the stage or compares things, 이/-가 keeps the spotlight strictly on the subject itself.
- New Information
- Used when the listener doesn't know what subject you are going to talk about yet.
In everyday life, you will hear this everywhere: from ordering food ('이것이 맛있어요?') to describing your feelings ('머리가 아파요'). It is the backbone of Korean sentence structure. Without it, sentences often feel incomplete or ambiguous, especially in written form or formal speech where particles are rarely dropped. Mastering this is the first real step toward thinking like a native Korean speaker.
The choice between 이 and 가 is determined entirely by phonetics—specifically, whether the preceding noun ends in a consonant or a vowel. This is a common pattern in Korean grammar designed to make speech flow more smoothly (euphony).
- Rule 1: Consonant Ending
- If the noun ends in a 'batchim' (final consonant), use 이. Example: 책 (book) + 이 = 책이.
- Rule 2: Vowel Ending
- If the noun ends in a vowel, use 가. Example: 사과 (apple) + 가 = 사과가.
동생이 학교에 가요. (The younger sibling goes to school.)
There are several irregular pronouns that change their form when combined with 가. This is one of the most common areas where learners make mistakes. You must memorize these specific changes:
- 나 (I - informal) + 가 = 내가 (NOT 나가)
- 저 (I - formal) + 가 = 제가 (NOT 저가)
- 너 (You - informal) + 가 = 네가 (NOT 너가, often pronounced '니가' in speech)
- 누구 (Who) + 가 = 누가 (NOT 누구가)
제가 하겠습니다. (I will do it.)
In complex sentences, 이/-가 is used to mark the subject of a nested or sub-clause, while the main topic of the whole sentence is marked by 은/는. For example: '저는 [친구가 준] 선물을 좋아해요' (I like the gift [that my friend gave me]). Here, '친구' (friend) is the subject of the action 'gave,' so it takes 가, while '저' (I) is the main topic of the entire sentence.
In natural, spoken Korean, particles are often dropped if the meaning is clear from the context. However, 이/-가 is retained more frequently than the object marker 을/를 because the subject is vital for understanding who is doing what. You will hear it constantly in K-Dramas during emotional declarations ('내가 미안해' - I am sorry) or in variety shows when identifying a specific person to perform a task ('유재석 씨가 하세요' - Mr. Yoo Jae-suk, you do it).
누구가 왔어요? (Who came?)
In formal news broadcasts or academic lectures, 이/-가 is used strictly and never omitted. It provides the grammatical precision required for reporting facts. For instance, '정부가 새로운 정책을 발표했습니다' (The government announced a new policy). Here, '정부가' clearly identifies the actor of the sentence.
- News & Reporting
- Used to clearly define the actor in headlines and reports to avoid ambiguity.
In casual conversation, there is a subtle difference when using 이/-가 versus dropping it. Dropping it makes the speech very fast and informal ('나 배고파' vs '내가 배고파'). Using the particle adds a tiny bit of emphasis to the subject. If you are in a restaurant and say '이게 맛있어요' (This is delicious), you are specifically pointing out this dish among others.
Lastly, in literature and storytelling, 이/-가 is used to introduce characters and settings. '옛날 옛적에 한 왕이 살았습니다' (Once upon a time, there lived a king). The king is new to the story, so 이 is used. Once he is established as the topic, the story might switch to using 은/는 to refer back to him.
The most frequent mistake for English speakers is confusing 이/-가 (subject marker) with 은/는 (topic marker). While both can often follow the word that seems like the subject, they have different 'flavors.' Using 이/-가 when you should use 은/는 can make your sentence sound too 'pointed' or like you are introducing a random new fact out of nowhere.
- The 'New Info' Rule
- Mistake: Using '은/는' to answer 'Who' questions. Correct: Use '이/-가'.
Another common error is applying the wrong particle based on the ending of the noun. Beginners often say '사람가' instead of '사람이' or '학교이' instead of '학교가'. Remember: Consonant + 이, Vowel + 가. A helpful way to remember is that '이' starts with a placeholder 'ㅇ', which 'invites' the preceding consonant to fill its spot.
Incorrect: 저가 학생입니다.
Correct: 제가 학생입니다.
Learners also struggle with the negation 아니다 (to not be). In English, we say 'I am not a student.' In Korean, the thing you are NOT must take the subject marker 이/-가. Many learners mistakenly use the object marker 을/를. Example: '저는 학생이 아니에요' (I am not a student) is correct; '저는 학생을 아니에요' is wrong.
Finally, remember the pronoun changes. '나' becomes '내', '저' becomes '제', and '너' becomes '네' ONLY when 가 is attached. You cannot say '나이' or '저이'. These irregular forms are used constantly, so using the incorrect '나가' or '저가' will immediately mark you as a beginner.
While 이/-가 is the standard subject marker, there are other particles that can function as subject markers in specific contexts. Understanding these helps you reach a higher level of fluency and politeness.
- 께서 (kkeseo)
- This is the honorific version of 이/-가. Use it when the subject is someone you must show high respect to, like a teacher, a boss, or your grandparents.
Example: 선생님께서 오십니다 (The teacher is coming).
- 에서 (eseo)
- Usually a location marker ('at/in'), but when the subject is an organization or a group acting as a single unit, '에서' can act as the subject marker.
Example: 우리 학교에서 우승했어요 (Our school won).
The most significant 'alternative' is 은/는 (the topic marker). While not a subject marker per se, it often replaces 이/-가 when the subject is already known or when you are comparing two things. Choosing between them is the 'eternal struggle' of Korean learners. A simple rule of thumb: use 이/-가 for specific details or new info, and 은/는 for general facts or when saying 'As for...'
비교 (Comparison):
1. 개가 있어요. (There is a dog - New info)
2. 개는 충성스러워요. (Dogs are loyal - General fact/Topic)
In very formal or archaic Korean, you might see 이 used even after vowels in historical texts, but in modern Korean, the distinction is strict. Also, in very informal speech, people might use -서 with numbers or people (e.g., '둘이서' - two people together), which functions similarly to a subject marker emphasizing the group.
How Formal Is It?
Fun Fact
Before the 16th century, '이' was used for almost all subjects, but '가' was introduced and became standard for vowel-ending words to make speech more distinct.
Pronunciation Guide
- Pronouncing '가' as 'ka' (it should be a soft 'g').
- Pronouncing '이' too long like 'eee'.
- Pausing between the noun and the particle.
- Not 'sliding' the consonant over to '이' (liaison).
- Confusing '내가' (I) with '네가' (you) due to similar vowel sounds.
Difficulty Rating
Easy to recognize in text once you know the rule.
Choosing between 이/가 and 은/는 is a lifelong challenge.
Pronunciation is easy, but remembering pronoun changes (내가) takes practice.
Can be hard to hear when spoken quickly or when liaison occurs.
What to Learn Next
Prerequisites
Learn Next
Advanced
Grammar to Know
Vowel/Consonant distinction for particles
이/가, 을/를, 은/는 follow this logic.
Pronoun contraction with '가'
나+가=내가, 저+가=제가.
Subject marker in '아니다' sentences
학생이 아니에요.
Subject marker in '있다/없다' sentences
돈이 있어요.
Honorific subject marker '께서'
부모님께서 말씀하셨어요.
Examples by Level
이름이 뭐예요?
What is (your) name?
이름 ends in a consonant, so '이' is used.
사과가 맛있어요.
The apple is delicious.
사과 ends in a vowel, so '가' is used.
제가 학생이에요.
I am a student.
저 + 가 becomes '제가'.
물이 있어요?
Is there water?
물 ends in a consonant, so '이' is used.
친구가 와요.
A friend is coming.
친구 ends in a vowel, so '가' is used.
돈이 없어요.
I don't have money.
돈 ends in a consonant, so '이' is used.
누가 먹었어요?
Who ate it?
누구 + 가 becomes '누가'.
이것이 책이에요.
This is a book.
이것 ends in a consonant, so '이' is used.
날씨가 아주 좋아요.
The weather is very good.
날씨 ends in a vowel, so '가' is used.
시간이 있어요?
Do you have time?
Common expression with '있다'.
한국말이 재미있어요.
Korean language is fun.
Subject marker used with an adjective.
어머니께서 요리하세요.
Mother is cooking.
Honorific subject marker '께서'.
배가 고파요.
I am hungry.
Literal: 'The stomach is hungry'.
가방이 무거워요.
The bag is heavy.
Subject marker used to describe a state.
어디가 아파요?
Where does it hurt?
Asking for a specific location of pain.
버스가 왔어요.
The bus has arrived.
Used for a new event/occurrence.
내가 어제 산 옷이 예뻐요.
The clothes I bought yesterday are pretty.
이/-가 used in both the sub-clause and main clause.
비가 오기 시작했어요.
It started raining.
Subject marker with a change of state.
누가 이 유리창을 깼어요?
Who broke this window?
'누가' focuses on identifying the specific person.
기분이 안 좋아요.
I'm not in a good mood.
Literal: 'The mood is not good'.
컴퓨터가 갑자기 고장 났어요.
The computer suddenly broke down.
Focus on the sudden event.
목소리가 정말 좋으시네요.
Your voice is really nice.
Focusing on a specific attribute.
열쇠가 어디 있는지 알아요?
Do you know where the keys are?
Subject marker in an indirect question.
이 문제가 너무 어려워요.
This problem is too difficult.
Specifying the particular problem.
정부에서 이 문제를 해결해야 합니다.
The government must solve this problem.
'에서' used as a subject marker for an organization.
바람이 불어서 꽃잎이 떨어져요.
The wind blows, so the petals fall.
Two subjects in a cause-and-effect sentence.
제 생각이 틀릴 수도 있어요.
My thought might be wrong.
Specifying the subject of the possibility.
도둑이 경찰에게 잡혔어요.
The thief was caught by the police.
Subject marker in a passive sentence.
아이들이 노는 소리가 들려요.
I hear the sound of children playing.
Subject marker in a noun-modifying clause.
이곳은 경치가 정말 아름답군요.
The scenery here is truly beautiful.
Subject marker '가' is replaced by '는' for the main topic, but '경치가' marks the specific subject.
누가 먼저 올지 모르겠어요.
I don't know who will come first.
Subject marker in a future-oriented sub-clause.
상황이 갈수록 나빠지고 있어요.
The situation is getting worse as time goes by.
Marking the evolving subject.
그의 말이 일리가 있네요.
What he says makes sense (has logic).
Idiomatic expression '일리가 있다'.
우리가 추구하는 가치가 무엇입니까?
What are the values we pursue?
Subject marker in a philosophical context.
드디어 기회가 찾아왔습니다.
The opportunity has finally arrived.
Personification of 'opportunity'.
마음이 가는 대로 하세요.
Do as your heart leads you.
Metaphorical use of the subject marker.
사건의 진상이 밝혀졌습니다.
The truth of the incident has been revealed.
Formal/Academic subject marker usage.
이 제도가 사회에 미치는 영향이 큽니다.
The impact this system has on society is great.
Complex sentence with a long subject phrase.
누구보다도 노력이 중요합니다.
Effort is more important than anything else.
Focusing on 'effort' as the key subject.
그 사람이 범인임이 틀림없다.
It is certain that he is the criminal.
Subject marker attached to a nominalized clause.
인간의 욕망이 끝이 없다.
Human desire has no end.
Philosophical statement with double subject.
역사가 우리를 심판할 것이다.
History will judge us.
Abstract subject in a formal declaration.
말이 씨가 된다는 말이 있다.
There is a saying that words become seeds (be careful what you say).
Proverbial usage.
세월이 유수와 같이 흐른다.
Time flows like running water.
Literary/Poetic expression.
본 위원회에서 다음과 같이 결정하였습니다.
This committee has decided as follows.
Highly formal institutional subject marker.
그의 행동이 시사하는 바가 크다.
What his actions suggest is significant.
Sophisticated academic structure.
민심이 천심이다.
The will of the people is the will of heaven.
Classical political philosophy.
운명이 우리를 갈라놓았다.
Fate has torn us apart.
Dramatic/Literary subject.
Common Collocations
Common Phrases
— What is your name? Literally: 'What is the name?'
처음 뵙겠습니다. 이름이 뭐예요?
— Where does it hurt? Used by doctors or concerned friends.
얼굴색이 안 좋네요. 어디가 아파요?
— How are you feeling? Literally: 'How is the mood?'
오늘 기분이 어때요?
— I don't have time. A very common excuse or statement of fact.
빨리 가야 해요. 시간이 없어요.
— A problem has occurred. Used when something goes wrong.
큰일 났어요. 문제가 생겼어요.
— Who did that? Used to find the culprit of an action.
방이 왜 이래요? 누가 그랬어요?
— I need money. A straightforward statement of need.
새 차를 사고 싶어서 돈이 필요해요.
— The weather is cold, isn't it? A common small talk starter.
오늘 날씨가 춥네요. 옷을 따뜻하게 입으세요.
— Where is the bathroom? A survival phrase for travelers.
실례합니다, 화장실이 어디예요?
— What is this? (Contraction of 이것이).
선물이에요? 이게 뭐예요?
Often Confused With
은/는 is for topics/contrast; 이/가 is for specific subjects/new info.
을/를 is for objects; 이/가 is for subjects.
의 is for possession; 이/가 is for the subject of the verb.
Idioms & Expressions
— To have a wide circle of acquaintances. Literally: 'The foot is wide.'
그 사람은 발이 넓어서 모르는 사람이 없어요.
Informal/Neutral— To be easily persuaded or gullible. Literally: 'The ear is thin.'
나는 귀가 얇아서 광고만 보면 사고 싶어.
Informal— To be a picky eater. Literally: 'The mouth is short.'
제 동생은 입이 짧아서 채소만 먹어요.
Informal— To be very generous or cook in large quantities. Literally: 'The hand is big.'
우리 어머니는 손이 커서 항상 음식을 많이 하세요.
Informal— To look familiar. Literally: 'The face is familiar.'
저 분은 어디서 본 것 같은데 낯이 익어요.
Neutral— To be very anxious or worried. Literally: 'The inside is burning.'
시험 결과가 안 나와서 속이 타요.
Informal— To be jealous. Literally: 'The stomach hurts' (often from seeing someone else's success).
친구가 새 차를 사니까 배가 아파요.
Informal— To be dumbfounded or amazing. Literally: 'The energy is blocked.'
이 경치는 정말 기가 막히네요!
Informal/Neutral— To feel a heavy burden of responsibility. Literally: 'The shoulders are heavy.'
팀장이 되니까 어깨가 무거워요.
Neutral— To have high standards. Literally: 'The eyes are high.'
그녀는 눈이 높아서 웬만한 남자는 안 좋아해요.
InformalEasily Confused
They sound very similar in standard pronunciation.
내가 means 'I'; 네가 means 'you'. In speech, 네가 is often pronounced '니가'.
내가 갈게 (I'll go) vs 니가 가 (You go).
Learners forget the consonant/vowel rule.
이 follows a consonant; 가 follows a vowel.
집이 (house) vs 학교가 (school).
Both can mark the 'main' word of a sentence.
이 focuses on the subject; 은 focuses on the topic or contrast.
개가 커요 (The dog is big - focus on dog) vs 개는 커요 (Dogs are big - topic of dogs).
Learners often say '누구가'.
누구 is the base word; 누가 is the form used with the subject marker.
누구예요? (Who is it?) vs 누가 했어요? (Who did it?).
Sentence Patterns
Noun(cons) + 이 있어요
책이 있어요.
Noun(vow) + 가 있어요
사과가 있어요.
Noun + 이/가 아니에요
의사가 아니에요.
Noun + 이/가 아프다/좋다
머리가 아파요.
Subject + [Verb clause] + Noun
내가 만든 빵이 맛있어요.
Organization + 에서 + Verb
우리 팀에서 이겼어요.
Noun + 이/가 ...음/기 + 이/가 틀림없다
그가 범인임이 틀림없다.
Double Subject pattern
한국은 산이 많아요.
Word Family
Related
How to Use It
Extremely High - It is one of the most used particles in the language.
Memorize It
Mnemonic
Think of 'I' (이) as a needle that fills the 'gap' of a consonant. Think of 'G' (가) as 'Go'—it moves fast after a vowel.
Visual Association
Imagine a noun ending in a blocky consonant. It needs the round '이' to roll smoothly. Imagine a noun ending in a vowel. It's open, so the '가' can just walk right in.
Word Web
Challenge
Try to label every noun in a short Korean paragraph as either a subject (이/가), a topic (은/는), or an object (을/를).
Word Origin
Koreanic origin. '이' is the older form, appearing in Middle Korean. '가' appeared later (around the 16th century) to help distinguish subjects in speech as the language evolved.
Original meaning: Purely grammatical function markers with no independent semantic meaning.
KoreanicCultural Context
Be careful to use '께서' for grandparents or bosses instead of '이/가' to avoid appearing rude.
English speakers often struggle because they want to use 'is' for '이/가', but '이/가' is just a marker, not a verb.
Practice in Real Life
Real-World Contexts
Introductions
- 제 이름이...입니다.
- 제 직업이...입니다.
- 고향이 어디예요?
- 누가 오셨어요?
Describing feelings
- 머리가 아파요.
- 기분이 좋아요.
- 배가 고파요.
- 목이 말라요.
Shopping
- 이게 얼마예요?
- 사이즈가 없어요.
- 색깔이 예뻐요.
- 다른 것이 있어요?
Restaurants
- 이게 맛있어요.
- 물이 필요해요.
- 반찬이 더 있어요?
- 누가 계산해요?
Weather
- 비가 와요.
- 눈이 내려요.
- 바람이 불어요.
- 날씨가 따뜻해요.
Conversation Starters
"오늘 날씨가 어때요? (How is the weather today?)"
"한국 음식이 맛있어요? (Is Korean food delicious?)"
"누가 제일 좋아해요? (Who do you like the most?)"
"이게 뭐예요? (What is this?)"
"어디가 제일 예뻐요? (Where is the prettiest?)"
Journal Prompts
오늘 기분이 어땠는지 써 보세요. (Write about how your mood was today.)
가장 좋아하는 한국 음식이 무엇인지 설명해 보세요. (Explain what your favorite Korean food is.)
가족 중에서 누가 가장 재미있어요? (Who in your family is the funniest?)
최근에 산 물건 중에서 무엇이 가장 마음에 들어요? (Which of the things you bought recently do you like the most?)
꿈이 무엇인지 적어 보세요. (Write down what your dream is.)
Summary
The particles '이' and '가' are the primary ways to mark a subject in Korean. Use '이' for words ending in a final consonant (e.g., 선생님이) and '가' for words ending in a vowel (e.g., 친구가). They focus the spotlight on the subject and are used for new information. Example: '날씨가 좋아요' (The weather is good).
- Identifies the subject (doer) of the sentence.
- Uses '이' after consonants and '가' after vowels.
- Essential for introducing new information or specific focus.
- Changes '나' to '내', '저' to '제', and '너' to '네'.
Related Content
More general words
몇몇
A2An unspecified small number of; some or a few.
조금
A1A little/a bit
적게
A1A little / Few
약간
A2A little; slightly; somewhat.
많이
A1A lot/much
잠시
A2For a moment; briefly.
잠깐
A2For a short time; a moment.
아까
A2A little while ago, earlier.
대해
A2About, concerning.
~에 대해서
A2Concerning or regarding a particular subject; about.
