매튜의 한국어 연습 블로그

Another short but sweet one. This one is something I've been searching for. I have a tendency to use "전에" and "후에" a lot in spoken Korean. However, it's more of a written expression. Using "후에" to express what will happen later isn't the worst thing one can do but it certainly isn't very native sounding. Therefore, the language nerd student rejoiced when I found this. I hope I can adopt it and similar expressions natively.

~고 나서, as you might have guessed, is used when one event has just finished and another is coming. But, how does this differ from vanilla "고" and "아/어서"? Seems we need a brief summary before going on:

(고)
오늘 친구가 만나고 영화 봤어요.
Today I met my friend and I saw a movie (but the friend didn't come with me).
The two events are not related. Both are in the past, though. Sequential order not implied (maybe I met my friend first or maybe I saw a movie first. Doesn't matter because we didn't see the movie together. It's just a recollection of stuff that happened today)

(아/어서)
오늘 친구가 만나서 영화 봤어요.
Today I met my friend and we saw a movie together.
The two events are related in sequential order. First I met my friend, and then we saw a movie.

The "~고 나서" grammar point is similar but has a vital difference. In this case, the first event (A) is already finished before the second event (B) will take place. The book I'm using gives a great example:

스티브는 저녁을 먹고 나서 도서관에 가서 공부를 해요.
After Steve eats dinner, he goes to the library to study.

Let's take a look at some other examples:
A: 언제 숙제 했어요? when did you do your homework?
B: 점심 먹고 나서 했어요. I did it after lunch, jerky.

A: 샤워 하고 나서 여친한테 전화 할 거야 After I take a shower, I'll call my girlfriend

Actually, I'm not super confident with the last grammar point. someone correct me.