The short version: -기 전에 = before: 자기 전에 (before sleeping). -(으)ㄴ 후에 = after: 먹은 후에 (after eating), with 다음에 and 뒤에 as everyday alternatives. -(으)ㄹ 때 = when: 갈 때, 어릴 때. Nouns attach directly: 수업 전에, 방학 때. The form shows the order of events, so -기 전에 never goes into the past, and 갈 때 and 갔을 때 describe different moments.
In English, “before”, “after” and “when” are separate words that come first in the clause. In Korean they are endings attached to the verb, which means the verb has to change shape to accept them. There are only three shapes to learn, and they follow one simple idea: the form tells the listener whether an event has happened yet, not whether the story is in the past.
Three endings on one timeline
-기 전에: before
Attach -기 전에 to any verb stem. There are no sound changes to worry about.
The point to remember is that the verb before 전에 never takes a past tense, even when the whole story is in the past. At the time of studying, coming to Korea had not happened yet. The past tense appears once, at the end.
-(으)ㄴ 후에: after
The after-ending changes slightly with the stem, exactly like the past modifier form.
| Stem ends in | Add | Example | Romanisation |
|---|---|---|---|
| a vowel | -ㄴ 후에 | 가다 → 간 후에 | gan hue |
| a consonant | -은 후에 | 먹다 → 먹은 후에 | meogeun hue |
| ㄹ | drop ㄹ, add ㄴ | 만들다 → 만든 후에 | mandeun hue |
| ㄷ (irregular) | ㄷ → ㄹ | 듣다 → 들은 후에 | deureun hue |
후에, 다음에 and 뒤에 all mean after. 후에 sounds slightly more formal, 다음에 is very common in conversation, and 뒤에 is also the word for behind. If you want to stress that the first action was fully finished, use -고 나서: 숙제를 하고 나서 놀아요 (I play after I've finished my homework).
-(으)ㄹ 때: when
| Stem ends in | Add | Example | Romanisation |
|---|---|---|---|
| a vowel | -ㄹ 때 | 가다 → 갈 때 | gal ttae |
| a consonant | -을 때 | 먹다 → 먹을 때 | meogeul ttae |
| ㄹ | nothing extra | 만들다 → 만들 때 | mandeul ttae |
| ㅂ (irregular) | ㅂ → 우 | 춥다 → 추울 때 | chuul ttae |
| a noun | + 때 | 방학 → 방학 때 | banghak ttae |
갈 때 vs 갔을 때: not there yet, or already there?
Just as with 전에, the form before 때 tells the listener whether the event had been completed. Korean adds the past marker -았/었- inside the clause when it had.
전에 vs 앞에, 후에 vs 뒤에
English uses “before” for time and “in front of” for place, and Korean makes the same distinction with different words.
Time
수업 전에sueop jeonebefore class
Place
집 앞에jip apein front of the house
수업 앞에 is a mistake for “before class”. 뒤에 is the exception that works for both: 수업 뒤에 (after class) and 집 뒤에 (behind the house).
Check yourself
Before, after or when, and has the event happened yet?
-기 전에 never takes the past.
After: consonant stem + 은 후에.
춥다 is ㅂ-irregular: 추울 때.
Time, not place: 전에.
You ate it in Korea, after arriving: 갔을 때.
아침 is already a time word, so it takes 에.
Tell your day in the right order
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Learn Korean with Hanguljo - FreeQuick reference
- Before
- Stem + 기 전에: 자기 전에. Noun + 전에: 수업 전에. Never past: 오기 전에.
- After
- Stem + (으)ㄴ 후에 / 다음에 / 뒤에: 간 후에, 먹은 후에, 만든 후에. Noun + 후에.
- When
- Stem + (으)ㄹ 때: 갈 때, 먹을 때, 추울 때, 어릴 때. Noun + 때: 방학 때.
- 갈 때 vs 갔을 때
- Not there yet / already there.
- Ago / later
- 삼 년 전에, 일주일 후에.
- Time words
- 아침, 오늘, 월요일, 주말 take 에, not 때.
- 전에 vs 앞에
- Time / place. 뒤에 = both.
Frequently asked questions
How do you say before in Korean?
Attach -기 전에 to the verb stem: 자기 전에 (before sleeping), 먹기 전에 (before eating). With nouns, use 전에 directly: 수업 전에. The verb never takes a past tense: 한국에 오기 전에, not 왔기 전에.
How do you say after in Korean?
Use -(으)ㄴ 후에: 간 후에 after a vowel stem, 먹은 후에 after a consonant. 다음에 and 뒤에 are common alternatives: 수업이 끝난 다음에. With nouns: 수업 후에.
What is the difference between 갈 때 and 갔을 때?
갈 때 means the going was not complete yet: on the way, or before leaving. 갔을 때 means you had already arrived. 한국에 갔을 때 친구를 만났어요 means you met your friend in Korea.
How do you say when I was young in Korean?
어릴 때, from the adjective 어리다 (to be young). 어릴 때 시골에 살았어요 means I lived in the countryside when I was young.
What is the difference between 전에 and 앞에?
전에 is about time: 수업 전에, before class. 앞에 is about place: 집 앞에, in front of the house. 뒤에 can be used for both: 수업 뒤에 (after class), 집 뒤에 (behind the house).
- National Institute of Korean Language, Standard Korean Language Dictionary (표준국어대사전): entries for 전, 후, 다음, 뒤 and 때.
- National Institute of Korean Language, Basic Korean Dictionary (한국어기초사전): learner entries for -기 전에, -(으)ㄴ 후에 and -(으)ㄹ 때.
- National Institute for International Education, TOPIK official site.