-거든 expresses conditional situations focused on uncertain future events, often followed by advice or suggestions. It means "if/when [future event happens]."
Structure
Verb/Adjective stem + -거든
Meaning: "If/when [future uncertain event], [advice/suggestion]"
Note: More casual and specific than -(으)면
Basic Pattern
All Verbs and Adjectives: -거든
No conjugation variations:
- 가다 → 가거든 (if/when you go)
- 오다 → 오거든 (if/when you come)
- 만나다 → 만나거든 (if/when you meet)
- 좋다 → 좋거든 (if it's good)
- 바쁘다 → 바쁘거든 (if you're busy)
Simple rule: Add -거든 to any stem
Core Characteristics
Future Uncertain Events
Focus on events that may or may not happen:
- 서울 가거든 연락하세요 (If you go to Seoul, contact me)
- 시간 있거든 놀러 오세요 (If you have time, come visit)
- 힘들거든 말하세요 (If it's hard, tell me)
Implies: The event is possible but not certain
Often with Advice/Suggestions
Followed by recommendations:
- 돈 필요하거든 말해 (If you need money, tell me)
- 배고프거든 먹어 (If you're hungry, eat)
- 모르거든 물어봐 (If you don't know, ask)
Common Usage Patterns
Future Visits/Meetings
When someone might come/go:
- 한국 오거든 연락하세요 (When you come to Korea, contact me)
- 서울 가거든 만나요 (If you go to Seoul, let's meet)
- 집에 오거든 전화해 (When you come home, call)
Conditional Offers
Offering help for future situations:
- 힘들거든 도와줄게 (If it gets hard, I'll help you)
- 필요하거든 가져가 (If you need it, take it)
- 궁금하거든 물어봐 (If you're curious, ask)
Giving Advice
Recommendations for future scenarios:
- 시간 있거든 쉬어 (If you have time, rest)
- 아프거든 병원 가 (If you're sick, go to the hospital)
- 늦거든 택시 타 (If you're late, take a taxi)
Politeness Levels
Casual: -거든
To friends, close relationships:
- 가거든 말해 (If you go, tell me)
- 오거든 연락해 (If you come, contact me)
Note: -거든 itself is already somewhat casual
Can't Add 요 Directly
❌ Wrong: 가거든요 ✅ Correct: 가거든 말해요 (If you go, tell me)
The polite ending goes on the result clause
Restrictions
Not for Commands
❌ Avoid with strong commands:
- 가거든 가세요 (awkward)
- Better: 가면 가세요
✓ Better with suggestions/offers:
- 가거든 연락하세요 (If you go, contact me) ✓
Future-Oriented
Works best for uncertain future:
- ✓ 내일 시간 있거든 와 (If you have time tomorrow, come)
- ✗ 어제 시간 있거든 (doesn't work with past)
Contrast with -(으)면
-거든 vs -(으)면
-거든: Future specific + advice
- 서울 가거든 연락해 (If you go to Seoul, contact me)
- → Specific future possibility
- → With suggestion/offer
-(으)면: General condition (any time)
- 서울 가면 연락하세요 (If you go to Seoul, contact me)
- → General, broader
- → Any type of result
Nuance Difference
-거든: "When that happens, [here's what to do]" -(으)면: "If this condition is met, [result]"
-거든 feels more:
- Casual
- Advisory
- Future-focused
- Conversational
Example Sentences
Future Plans
- 부산 가거든 연락해 (If you go to Busan, contact me)
- 이사하거든 알려줘 (If you move, let me know)
- 결혼하거든 초대해 줘 (If you get married, invite me)
Conditional Help
- 힘들거든 말해 (If it's hard, tell me)
- 필요하거든 빌려줄게 (If you need it, I'll lend it)
- 모르거든 가르쳐 줄게 (If you don't know, I'll teach you)
Making Arrangements
- 도착하거든 전화해 (When you arrive, call)
- 끝나거든 연락해 (When you finish, contact me)
- 시간 되거든 만나자 (When you have time, let's meet)
Example Dialogues
Dialogue 1: Future Visit
A: 다음 주에 서울 갈 거예요.
(I'm going to Seoul next week.)
B: 그래? 오거든 우리 집에 놀러 와.
(Really? If you come, visit my house.)
Dialogue 2: Offering Help
A: 숙제가 너무 어려워요.
(The homework is too difficult.)
B: 힘들거든 도와줄게요.
(If it gets hard, I'll help you.)
Dialogue 3: Making Plans
A: 이번 주말에 시간 있어?
(Do you have time this weekend?)
B: 모르겠어. 시간 있거든 연락할게.
(I don't know. If I have time, I'll contact you.)
Dialogue 4: Advice
A: 요즘 너무 피곤해.
(I'm so tired lately.)
B: 피곤하거든 좀 쉬어.
(If you're tired, rest a bit.)
With Question Words
Asking for Future Info
Questions + -거든:
- 언제 오거든 연락해 (Whenever you come, contact me)
- 뭐 필요하거든 말해 (Whatever you need, tell me)
- 어디 가거든 사진 보내 (Wherever you go, send pictures)
Common Expressions
Everyday Uses
- 시간 있거든 와 (If you have time, come)
- 심심하거든 전화해 (If you're bored, call)
- 배고프거든 먹어 (If you're hungry, eat)
- 추우거든 입어 (If you're cold, wear it)
- 아프거든 말해 (If you're sick, tell me)
Travel/Moving
- 여행 가거든 연락해 (If you travel, contact me)
- 이사하거든 주소 보내 (If you move, send your address)
- 출장 가거든 알려줘 (If you go on business trip, let me know)
Common Mistakes
❌ Incorrect: 가거든요
Can't add 요 directly to -거든
✅ Correct: 가거든 말해요
요 goes on result clause
❌ Incorrect: 갔거든 (for past)
-거든 is future-oriented
✅ Correct: 갔으면 or 가면
Use other forms for past conditions
❌ Incorrect: 가거든 가세요
Too commanding
✅ Correct: 가거든 연락하세요
Better with suggestions
Regional and Usage Notes
More Common in Spoken Korean
Casual conversation:
- ✓ Natural in daily speech
- ✗ Less common in formal writing
- ✓ Good for friendly advice
Alternative: -(으)면
Can usually replace with -(으)면:
- 가거든 연락해 → 가면 연락해
- Both acceptable, -거든 more casual/advisory
Summary Table
| Situation | Example | Meaning |
|---|---|---|
| Future visit | 오거든 전화해 | If you come, call |
| Need help | 필요하거든 말해 | If you need it, tell me |
| Conditional advice | 힘들거든 쉬어 | If it's hard, rest |
| Making plans | 시간 있거든 만나자 | If you have time, let's meet |
Key Takeaways
✅ Future conditional: For uncertain future events
✅ All verbs/adjectives: Just add -거든
✅ Often with advice: Followed by suggestions
✅ Casual tone: More conversational than -(으)면
✅ Not for commands: Better with recommendations
✅ Future-focused: Doesn't work well with past
-거든 is a useful casual conditional form for giving advice about future uncertain situations. While -(으)면 is more versatile and common, -거든 adds a friendly, advisory tone that's perfect for casual conversations with friends about future possibilities.