A/V-거든 grammar = if (something is true), then ~express condition in casual conversation

A/V-거든 grammar = if (something is true), then ~ express condition in casual conversation

Usage:
- A/V-거든 is used in mid-sentence to express a conditional statement in casual conversation= "if something is true, then..." 

- A/V-거든(요) is used in sentence-final to respond to a question or statement to provide the reason or thinking.

See: A/V-거든(요) grammar = because ~respond to a question or statement to provide a reason or thinking

Tense

Adjective/Verb + 거든:

크다 --> 크거든  (if it is big...)

바쁘다 --> 바쁘거든 (if you are busy...)

있다 --> 있거든 (if you have...)

피곤하다 --> 피곤하거든 (if you feel tired...)

물어보다 --> 물어보거든 ( if you ask ...)

오다 --> 오거든 (if you come...)

먹다 --> 먹거든 (if you eat ...)

Noun + (이)거든:

친구 --> 친구거든 (if he is a friend...)

학생 --> 학생이거든 (if you are a student...)

주부 --> 주부거든 (if she is a housewife,...)

Examples

1. 엄마, 이렇게 더운데 꼭 같이 가야 돼요?
- 가기 싫거든 안 가도 돼. 나 혼자 다녀올게.

Mom, do I really have to go with you in this heat?
- If you don’t want to go, then you don’t have to. I will go by myself.

2. 여보 이 옷 어때요? 저에게 안 어울리는 것 같지요?
- 이 옷이 마음에 안 들거든 다른 가게에 가 봅시다.

Dear, how are these clothes? Wouldn’t you agree they’re not really my style?
- If you don’t like these, then let’s go to another store.

3. 바쁜지 않거든 잠깐 만납시다.

If you are not busy, then let’s meet for a while.

4. 할 말이 있거든 오늘 일이 끝난 후에 하세요.

If you have something to say, then let me know after work today.

5. 친한 친구거든  여행을 같이 가자고 해요.

If he is a close friend, then ask him to go on the trip together.

6. 피곤하거든 오늘은 일찍 퇴근하세요.

If you are tired, then leave work early today.

7. 다른 사람들이 물어보거든 아파서 못 갔다고 전해 주세요.

If my friends ask (about me), then please tell them that I am sick so that I can’t go.

8. 비가 그치거든 바로 출발하세요.

If the rain has stopped, then please depart now.

9. 머리가 아프거든 이 약을 드셔 보세요.

If you have a headache, then drink this medicine.

10. 요즘 많이 바쁘거든 나중에 만납시다.

If you are busy recently, then let meet later.

11. 목이 아프거든 빨리 병원에 가세요.

If you have a sore throat, go to the hospital quickly.

12. 신발을 신어 보고 작거든 말해 주세요.

Try on the shoes and tell me if they are small.

13. 공항에 도착하거든 이 번호로 전화하세요.

Call this number when you arrive at the airport.

14. 친구가 전화를 안 받거든 문자를 보내세요.

If your friend doesn't answer the phone, text them.

15. 컴퓨터가 느리거든 끄고 다시 켜 보세요.

If your computer is slow, try to restart it.

16. 모르는 단어가 있거든 사전을 찾아보세요.

If there is a word you do not know, look up the dictionary.

17. 밤에 잠이 안 오거든 따뜻한 우유를 마셔 보세요.

If you can't sleep at night, try drinking warm milk.

18. 시험을 보기 전에 긴장되거든 조용한 음악을 들어 보세요.

If you're nervous before a test, try to listen to some quiet music.

Specific usage:
- The grammar is often used in imperative form (-세요, 십이요), propositive form (읍시다), or a form with subject’s will or conjecture (-겠-, -(ㅇ)ㄹ 것이다, or -(으)려고 하다).

e.g.

집에 도착하거든 전화 꼭 하세요.

Make sure to call me when you arrive home.

방학을 하거든 배낭여행을 가겠어요. 

If I am on vacation, I'll go backpacking.

어려운 일이 생기거든 언제든지 도와줄게요.

If you have any difficulties, I will always help you.

Comparison between -거든 and -거든요.

1. 거든 : used in mid-sentence, and express a conditional statement

E.g. 한국말이 어렵거든 매일 쓰기랑 듣기랑 읽기랑 말하기를 해야 해요.

If Korean is really difficult, then you have to write, listen, read, and speak everyday.

2. 거든요 : used in sentence-final, and express a reason known only by speaker.

E.g. 왜 점심을 안 먹었어요? 

- 아침을 너무 많이 먹었거든요.

Why didn't you eat lunch?

- Because I ate too much in the morning.