-고
and — joining clauses
Links two sentences into one. Attaches straight to the stem with no vowel rule, and carries no cause or condition — just “and then” or “and also.”
Build it
Pick a verb
When to use it
-고 does two things that English also lumps under “and.” It lists facts in no particular order: 동생은 키가 크고 저는 작아요. And it puts actions in sequence: 밥을 먹고 학교에 갔어요. Which reading applies depends on whether the verbs describe states or actions.
Tense normally goes only on the final clause. 밥을 먹고 갔어요 is past throughout, even though 먹고 looks tenseless. Putting 었 in both clauses is possible but marks them as two separate, unconnected events.
The subjects of the two clauses can differ freely, which sets -고 apart from -아서/어서. And note the limit: -고 joins clauses only. To join two nouns you need 하고 or 와/과.
How to attach it
| Situation | Form | Example |
|---|---|---|
| Any verb or adjective | -고 | 먹다 → 먹고 |
| ㄹ stems keep the ㄹ | -고 | 만들다 → 만들고 |
| 이다 | -이고 | 학생이고 |
| Tense on the last clause | plain stem + 고 | 먹고 갔어요 |
| Separate past events | -았/었고 | 먹었고 잤어요 |
| Joining nouns takes | 하고, 와/과 | 빵하고 우유 — not 빵이고 |
In use
저녁을 먹고 산책했어요.
I had dinner and then went for a walk.
이 식당은 싸고 맛있어요.
This restaurant is cheap and tasty.
저는 커피를 마시고 친구는 차를 마셔요.
I drink coffee and my friend drinks tea.
숙제를 하고 잤어요.
I did my homework and went to bed.
그 사람은 학생이고 저는 회사원이에요.
He’s a student and I’m an office worker.
손을 씻고 밥을 드세요.
Wash your hands and then eat.
Compared with
-아서/어서
Both can chain actions, but -아서 means the first action makes the second possible or connected. -고 simply reports one after the other. The subjects must match with -아서; with -고 they need not.
친구를 만나고 영화를 봤어요. (met, then saw a film) / 친구를 만나서 영화를 봤어요. (met up and saw a film together)
하고, 와/과
-고 joins clauses; these join nouns. English “and” covers both, which is where the mix-up starts.
빵을 사고 집에 갔어요. (bought bread, went home) / 빵하고 우유를 샀어요. (bought bread and milk)
-(으)면서
-고 puts actions in a row; -(으)면서 has them happening at the same time.
밥을 먹고 텔레비전을 봤어요. (ate, then watched) / 밥을 먹으면서 텔레비전을 봤어요. (ate while watching)
Watch out
빵이고 우유를 샀어요.
빵하고 우유를 샀어요.
-고 cannot join two nouns inside one action. Use 하고, 와/과, or (이)랑.
어제 밥을 먹었고 잤어요.
어제 밥을 먹고 잤어요.
For a natural sequence, tense sits only on the final verb. Marking both makes the two events sound unrelated.
배가 고프고 밥을 먹었어요.
배가 고파서 밥을 먹었어요.
-고 states two facts side by side and cannot express cause. If the first explains the second, you need -아서/어서.
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