-다가
in the middle of doing, and then
Breaks off one action to start another. The first action was under way and did not finish — which is what separates it from -고.
Build it
Pick a verb
When to use it
Attach -다가 to the plain stem, often shortened to -다 in speech: 학교에 가다가 친구를 만났어요 — I was on my way to school when I ran into a friend. The going was interrupted.
The subject must be the same in both clauses, as with -(으)면서.
Adding the past marker changes the picture entirely. -았/었다가 means the first action completed and was then reversed or followed by something opposite: 학교에 갔다가 왔어요 (I went to school and came back). Compare 가다가 왔어요, where you never arrived.
It also marks an unwanted result: 뛰어가다가 넘어졌어요. Here the first action caused the second, and the outcome is usually negative.
How to attach it
| Situation | Form | Example |
|---|---|---|
| Any verb | -다가 | 가다 → 가다가 |
| Spoken short form | -다 | 가다 만났어요 |
| Interrupted action | plain stem | 가다가 왔어요 — never arrived |
| Completed, then reversed | -았/었다가 | 갔다가 왔어요 — went and returned |
| Unwanted result | -다가 | 뛰어가다가 넘어졌어요 |
| Same subject | required | different subjects need -는 동안 |
In use
학교에 가다가 친구를 만났어요.
I ran into a friend on my way to school.
텔레비전을 보다가 잠이 들었어요.
I fell asleep while watching TV.
뛰어가다가 넘어졌어요.
I fell over while running.
은행에 갔다가 바로 집에 왔어요.
I went to the bank and came straight home.
책을 읽다가 재미없어서 그만뒀어요.
I was reading the book but stopped because it was dull.
저녁을 만들다가 손을 베었어요.
I cut my hand while making dinner.
Compared with
-고
-고 says the first action finished; -다가 says it was cut short. The difference is whether you arrived.
학교에 가고 친구를 만났어요. (got there, then met) / 학교에 가다가 만났어요. (met on the way)
-(으)면서
-(으)면서 has both actions running together; -다가 stops one to begin the other.
음악을 들으면서 공부해요. (both at once) / 공부하다가 음악을 들었어요. (stopped studying to listen)
-았/었다가
Adding tense flips the meaning from “interrupted” to “completed and then reversed.” A frequent source of confusion.
가다가 왔어요. (turned back on the way) / 갔다가 왔어요. (went there and came back)
Watch out
제가 요리하다가 동생이 왔어요.
제가 요리하는 동안 동생이 왔어요.
-다가 requires one subject for both clauses. With two people, use -는 동안.
은행에 가다가 왔어요. — meaning “I went and came back”
은행에 갔다가 왔어요.
Without the past marker, you never reached the bank. 갔다가 says you got there and then returned.
공부하다가 친구가 전화했어요.
공부하다가 친구한테 전화했어요.
Same-subject rule again: the person who was studying has to be the one who then phones.
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