Overview
때문에 literally means "because of" and is used to clearly state a reason or cause. It works in two main patterns:
| Pattern | Structure | Example |
|---|---|---|
| With nouns | Noun + 때문에 | 비 때문에 (because of rain) |
| With verbs/adjectives | Verb stem + 기 때문에 | 바쁘기 때문에 (because of being busy) |
때문에 is more explicit and formal than ~아/어서 or ~(으)니까. It strongly highlights the cause.
Part 1: Noun + 때문에
Attach 때문에 directly after a noun to mean "because of [noun]."
Basic examples
| Noun | + 때문에 | Meaning |
|---|---|---|
| 비 (rain) | 비 때문에 | because of rain |
| 일 (work) | 일 때문에 | because of work |
| 시험 (exam) | 시험 때문에 | because of the exam |
| 돈 (money) | 돈 때문에 | because of money |
| 감기 (cold) | 감기 때문에 | because of a cold |
In sentences
- 비 때문에 경기가 취소됐어요. (The game was canceled because of rain.)
- 시험 때문에 잠을 못 잤어요. (I couldn't sleep because of the exam.)
- 일 때문에 바빠요. (I'm busy because of work.)
- 교통사고 때문에 길이 막혀요. (The road is jammed because of a traffic accident.)
- 감기 때문에 학교에 못 갔어요. (I couldn't go to school because of a cold.)
With people (pronouns)
때문에 can be used with people to mean "because of [person]":
- 저 때문에 죄송합니다. (I'm sorry, it's because of me.)
- 너 때문에 늦었어. (I was late because of you.)
- 그 사람 때문에 힘들었어요. (It was hard because of that person.)
Part 2: Verb/Adjective Stem + 기 때문에
To use 때문에 with a verb or adjective, first turn the verb into a noun using ~기 (nominalization), then add 때문에.
Formation
| Dictionary form | Stem + 기 | + 때문에 | Full form |
|---|---|---|---|
| 바쁘다 (to be busy) | 바쁘기 | 바쁘기 때문에 | because of being busy |
| 비가 오다 (to rain) | 비가 오기 | 비가 오기 때문에 | because it rains |
| 돈이 없다 (no money) | 돈이 없기 | 돈이 없기 때문에 | because there is no money |
| 시간이 많다 (lots of time) | 시간이 많기 | 시간이 많기 때문에 | because there is lots of time |
With tense
You can add past tense before 기 때문에:
| Tense | Formation | Example |
|---|---|---|
| Present | Stem + 기 때문에 | 바쁘기 때문에 (because I'm busy) |
| Past | Stem + 았/었기 때문에 | 바빴기 때문에 (because I was busy) |
- 늦게 일어났기 때문에 지각했어요. (I was late because I woke up late.)
- 열심히 공부했기 때문에 시험을 잘 봤어요. (I did well on the exam because I studied hard.)
- 날씨가 춥기 때문에 집에 있을 거예요. (Because the weather is cold, I'll stay home.)
- 한국에 살았기 때문에 한국어를 잘해요. (I speak Korean well because I lived in Korea.)
Part 3: Noun + 때문이에요 (It's because of...)
When 때문에 is at the end of a sentence (as the predicate), it becomes 때문이에요 (polite) or 때문입니다 (formal).
- 다 비 때문이에요. (It's all because of the rain.)
- 제 잘못이 아니에요. 그 사람 때문이에요. (It's not my fault. It's because of that person.)
- 이게 다 돈 때문이에요. (This is all because of money.)
With verbs: ~기 때문이에요
- 제가 늦은 건 버스가 안 왔기 때문이에요. (The reason I was late is because the bus didn't come.)
- 성공한 건 열심히 했기 때문이에요. (The reason for success is because I worked hard.)
Comparing 때문에 with ~아/어서 and ~(으)니까
| Feature | ~아/어서 | ~(으)니까 | ~때문에 |
|---|---|---|---|
| Tone | Casual, soft | Assertive | Formal, explicit |
| With commands | X | O | O (less common) |
| With suggestions | X | O | O (less common) |
| Past tense on 1st clause | X | O | O (았/었기 때문에) |
| With nouns | X (verb connector) | X (verb connector) | O (Noun + 때문에) |
| Formality | Conversational | Conversational | More formal/written |
Same meaning, different nuance
All three can express "because I was busy":
| Connector | Korean | Nuance |
|---|---|---|
| ~아/어서 | 바빠서 못 갔어요 | Natural, conversational |
| ~(으)니까 | 바쁘니까 못 갔어요 | Assertive, justifying |
| ~기 때문에 | 바쁘기 때문에 못 갔어요 | Formal, explicit, written |
Common Patterns and Collocations
때문에 with common nouns
| Korean | English |
|---|---|
| 일 때문에 | because of work |
| 날씨 때문에 | because of the weather |
| 건강 때문에 | because of health |
| 돈 때문에 | because of money |
| 가족 때문에 | because of family |
| 시간 때문에 | because of time |
| 스트레스 때문에 | because of stress |
| 코로나 때문에 | because of COVID |
N 때문에 vs. N(으)로 인해
In very formal or written Korean, ~(으)로 인해 is used instead of 때문에:
- 폭우로 인해 행사가 취소되었습니다. (The event was canceled due to heavy rain.)
This is common in news, official documents, and academic writing.
때문에 with Questions
때문에 works naturally in questions:
- 뭐 때문에 왔어요? (What did you come for? / Because of what?)
- 누구 때문에 화났어요? (Who are you angry at? / Because of whom?)
- 왜 때문에... (X) → Just use 왜 (why)
Note: "왜 때문에" is redundant because 왜 already means "why." Use either 왜 or 뭐 때문에.
Common Mistakes
| Mistake | Correction | Why |
|---|---|---|
| 바쁘다 때문에 | 바쁘기 때문에 | Verbs need ~기 before 때문에 |
| 왜 때문에 | 왜 / 뭐 때문에 | 왜 = why, so 왜 때문에 is redundant |
| 비 때문에서 | 비 때문에 | 때문에 doesn't take particles |
| 때문에 at sentence end | 때문이에요 | Use 이다 form at sentence end |
Summary
- Noun + 때문에 = "because of [noun]" -- attach directly to nouns.
- Verb stem + 기 때문에 = "because [verb]" -- nominalize with 기 first.
- At the end of a sentence, use 때문이에요 / 때문입니다.
- 때문에 is more explicit and formal than ~아/어서 or ~(으)니까.
- Past tense: use ~았/었기 때문에 for past reasons with verbs.
- Avoid the redundant 왜 때문에 -- use 왜 or 뭐 때문에 instead.