1) adjective/verb + 고 – ‘and’ : Connect the same two sentences.
미나 씨는 예쁘고 친절해요. Mina is pretty and kind.
날씨가 춥고 눈이 많이 와요. It is cold and it snows a lot.
민호 씨는 의사이고 민호 씨 아내는 선생님이에요. Minho is a doctor and Minho’s wife is a teacher.
2) verb +고 – ‘and then’. Time order(the first action happens and then the second action). Two actions are not really related.
보통 게임을 하고 잠을 자요. I usually play game and then go to bed.
밥을 먹고 텔레비전을 봤어요. I ate and then watched TV.
청소하고 설거지했어요. I cleaned and then washed dishes.
음악을 듣고 영화를 볼 거예요. I will listen to music and then watch a movie.
음식을 만들고 청소할 거예요. I will cook and then clean.
선물을 사고 집에 왔어요. I bought a gift and came home.
친구를 만나고 영화를 볼 거예요. I am going to meet my friend, and then I will watch a movie (not with the friend).
1) adjective/verb+아/어/여서 – It means ‘so(reason+result)’. Tenses should be on the second sentence. And you cannot use ‘suggestion’, ‘command’ or ‘requesting’ on the second sentence. If you learn more, click here to look at –으니까 and –아/어/여서.
일찍 일어나서 피곤해요. I woke up early, so I am tired.
피곤해서 커피를 많이 마셨어요. I was tired, so I drank a lot of coffee.
커피를 많이 마셔서 잠을 못 잤어요. I drank a lot of coffee, I could not sleep.
잠을 못 자서 피곤해요. I could not sleep well, I am tired.
피곤해서 일찍 집에 가세요. (X) => 피곤하니까 일찍 집에 가세요. (O)
2) verb+아/어/여서 – It means ‘While you maintain the first action, and then’ or ‘on that situation’, so ‘the first action must happens for the second sentence’. Two actions are related.
일찍 일어나서 운동했어요. I get up early, (while I am up) and then exercise.
앉아서 이야기해도 돼요. You can sit down, (while you sit down) and then tell me.
누워서 텔레비전을 보지 마세요. Don’t lay down, (while you lay down) and then watch TV.
불고기를 만들어서 (불고기를) 먹었어요. I made Bulgogi, and then eat it.
학교에 가서 (학교에서) 공부했어요. I went to school, and then I study (there).
친구를 만나서 (친구하고) 영화를 봤어요. I met my friend, and then I watch a movie with her.
* 친구를 만나고 영화를 봤어요. I met my friend, and then I watch a movie by myself.
선물을 사서 (그 선물을) 친구한테 줬어요. I bought a gift, and then I gave it to my friend.
* 선물을 사고 친구를 만났어요. I bought a gift, and then I met my friend.
As a result,
-고 : two actions are not related.
-아/어/여서 : two actions are related.
and -아/어/여서 is mostly used for these sentences.
1) if you go somewhere, and you do something (there)
2) if you make something, and you do something (with that)
3) if you do something, and you do something(while you do the first action)