-거든
If, When (Casual)
-거든 is a conversational connector used in two main ways: as a conditional ('if' or 'when') or to provide a reason or background information ('because' or 'you see...').
How It Works
-거든 is a versatile ending primarily used in spoken Korean. Its meaning is heavily dependent on its position and the type of sentence that follows.
1. Conditional Usage (If/When)
This usage connects two clauses, where the first clause with -거든 sets a condition for the second. It's a stronger, more certain condition than -(으)면.
- Structure: [Verb/Adjective Stem] + -거든, [Command / Suggestion / Promise]
- Key Point: The second clause is almost never a simple declarative statement about a fact or habit. It must be a command, suggestion, proposal, or a statement of the speaker's intention.
- Example: 도착하거든 전화해. (When you arrive, call me.) - This is a command.
- Example: 바쁘지 않거든 좀 도와줘. (If you're not busy, please help me a bit.) - This is a request.
2. Reason/Background Usage (Because/You see...)
This usage appears at the end of a sentence to provide context or a reason for what was just said or what is happening. It's often used to answer a 'why' question, either stated or implied.
- Structure: [Sentence explaining a situation]. [Sentence ending in -거든].
- Key Point: It adds a nuance that the speaker is letting the listener in on some information. It's very conversational.
- Example: A: 왜 이렇게 기분이 좋아 보여요? (Why do you look so happy?)
B: 오늘 월급날이거든. (It's because today is payday, you see.)
Tense and Form:
- It attaches directly to the stem regardless of a final vowel or consonant: 먹다 → 먹거든, 가다 → 가거든, 좋다 → 좋거든.
- It can be used with the past tense marker -았/었-: 숙제를 다 했거든 놀러 가. (If you've finished your homework, go play.)
- It attaches to 이다 as 이거든/아니거든.
Examples (5)
- 한국에 도착하거든 바로 전화해 주세요.
When you arrive in Korea, please call me right away.
Word by Word: To Korea arrive-if right away call please give.
This shows the conditional usage of -거든. The condition is 'arriving in Korea', and it is followed by a command/request 'please call me'.
- A: 왜 이렇게 서둘러요?
B: 곧 기차가 출발하거든.
A: Why are you in such a hurry? B: Because the train is about to depart.
Word by Word: A: Why like this hurry? B: Soon train departs-because.
This shows the reason/background usage. B explains the reason for hurrying. The -거든 ending implies "The reason is..." or "You see, the train is leaving."
- 그 책을 다 읽었거든 저 좀 빌려주세요.
If/When you've finished reading that book, please lend it to me.
Word by Word: That book all read-if I a little please lend.
This example uses the past tense marker -었- with -거든 to set a condition based on a completed action.
- 시간이 괜찮거든 우리 저녁이나 같이 먹자.
If you have time, let's have dinner or something together.
Word by Word: Time is okay-if we dinner or something together let's eat.
Here, -거든 is attached to an adjective (괜찮다) and is followed by a suggestion (-자).
- A: 이 옷 정말 예쁘네요!
B: 어제 세일해서 샀거든.
A: These clothes are really pretty! B: (That's because) I bought them on sale yesterday.
Word by Word: A: This clothes really pretty! B: Yesterday sale-so bought-because.
B is providing the background information for why they have these new, pretty clothes. It's a conversational way to explain the situation.
Common Mistakes
Using -거든 for general truths or facts instead of -(으)면.
Not Quite물이 100도가 되거든 끓어요.Better물이 100도가 되면 끓어요.-거든 is used for specific conditions, usually followed by a command or suggestion. For general, scientific facts like 'water boils at 100 degrees', you must use the general conditional -(으)면.
Following the conditional -거든 with a simple descriptive statement instead of a command or suggestion.
Not Quite퇴근하거든 차가 많이 막혔어요.Better퇴근하니까 차가 많이 막혔어요.The conditional -거든 sets up an expectation for a command, suggestion, or will (e.g., '퇴근하거든 전화해' - 'When you get off work, call me'). It cannot be followed by a simple past-tense observation. To state a reason or sequence, -(으)니까 or -고 would be more appropriate.
Learn This First
To use casual conditionals 'if/when', you need conjugation and conditional knowledge.
Related Patterns
- -(으)니까So, Because
Both can express a reason. -(으)니까 is a standard reason connector. The 'reason' usage of -거든 is more conversational, used at the end of a sentence to provide background information that the listener might not know.
- -잖아You Know, ... Right?
Both are conversational sentence endings that provide information. -거든 introduces a reason or new information ('You see...'). -잖아 confirms information the speaker thinks the listener already knows ('...you know').
- -자마자As Soon as
While conditional -거든 can mean 'when', -자마자 specifically means 'as soon as' and emphasizes the immediacy of the following action. '도착하거든' means 'when you arrive (at some point)', while '도착하자마자' means 'the very moment you arrive'.