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When Connector: -을 때, -자마자, -고 나서

Quick Reference

-을 때: "when, at the time of" (general timing) -자마자: "as soon as, right after" (immediate succession) -고 나서: "after doing" (after completion with gap) Key Difference: -을 때 = simultaneous or general time | -자마자 = immediate | -고 나서 = sequential with completion

Detailed Explanation

Korean has several ways to express temporal relationships. Each pattern carries specific nuances about timing, sequence, and the relationship between events.

Formation Rules

-을 때

Based on final consonant:

  1. Stem ends in vowel or ㄹ → ㄹ 때
  2. 가다 → 갈 때
  3. 만들다 → 만들 때 (ㄹ stays)

  4. Stem ends in consonant → 을 때

  5. 먹다 → 먹을 때
  6. 읽다 → 읽을 때

  7. For past tense: Add 았/었 before 을 때

  8. 갔을 때, 먹었을 때

  9. For adjectives: Same rules apply

  10. 춥다 → 추울 때
  11. 바쁘다 → 바쁠 때

  12. For nouns: Noun + 일 때

  13. 학생 → 학생일 때
  14. 어렸다 → 어렸을 때

-자마자

Simple formation for all verbs:

  1. All verbs: Stem + 자마자
  2. 가다 → 가자마자
  3. 먹다 → 먹자마자
  4. 듣다 → 듣자마자

Note: Cannot be used with adjectives or nouns

-고 나서

Simple formation for all verbs:

  1. All verbs: Stem + 고 나서
  2. 가다 → 가고 나서
  3. 먹다 → 먹고 나서
  4. 공부하다 → 공부하고 나서

Note: Only used with action verbs (cannot use with adjectives)

Detailed Usage

1. -을 때: "When/At the time of"

Most versatile time expression. Used for:

A. Simultaneous Actions

Actions happening at the same time:

  1. 음악을 들을 때 공부해요. I study when I listen to music. (while)

  2. 밥을 먹을 때 텔레비전을 봐요. I watch TV when I eat. (while eating)

B. General Time Reference

General point in time when something happens:

  1. 시간이 있을 때 연락하세요. Contact me when you have time.

  2. 날씨가 좋을 때 산책하러 가요. When the weather is nice, I go for a walk.

C. Past Time Reference (았/었을 때)

Referring to a specific past time:

  1. 어렸을 때 부산에 살았어요. When I was young, I lived in Busan.

  2. 한국에 갔을 때 친구를 만났어요. When I went to Korea, I met a friend.

D. Future Time Reference

  1. 한국에 갈 때 선물을 사 올게요. When I go to Korea, I'll buy you a gift.

2. -자마자: "As soon as/Right after"

Emphasizes immediate succession. The second action happens right after the first with no gap.

A. Immediate Actions

  1. 집에 오자마자 잤어요. As soon as I came home, I slept.

  2. 아침에 일어나자마자 커피를 마셔요. As soon as I wake up in the morning, I drink coffee.

  3. 전화를 받자마자 나갔어요. As soon as I received the call, I left.

B. Instant Reactions

  1. 그 소식을 듣자마자 기뻤어요. As soon as I heard the news, I was happy.

  2. 시험이 끝나자마자 여행을 갔어요. As soon as the exam ended, I went on a trip.

3. -고 나서: "After doing"

Emphasizes completion and allows for a time gap between actions.

A. Sequential Actions with Completion

  1. 숙제를 하고 나서 놀았어요. After doing homework, I played.

  2. 밥을 먹고 나서 설거지를 해요. After eating, I do the dishes.

B. Emphasizing Completion

  1. 이 책을 다 읽고 나서 드릴게요. After I finish reading this book, I'll give it to you.

  2. 생각하고 나서 결정할게요. After thinking about it, I'll decide.

C. With Time Expressions

Can include time gap between actions:

  1. 회의가 끝나고 나서 30분 후에 만나요. Let's meet 30 minutes after the meeting ends.

Key Differences

-을 때 vs -자마자 vs -고 나서

Feature -을 때 -자마자 -고 나서
Timing During/when Immediately after After completion
Gap allowed Simultaneous or gap No gap Gap allowed
Emphasis Time point Immediacy Completion
With adjectives ✓ Yes ✗ No ✗ No
Past form 았/었을 때 No past form No past form

Comparison Examples

Same situation, different nuances:

  1. -을 때: 학교에 갈 때 친구를 만났어요. When I was going to school, I met a friend. (during the journey)

  2. -자마자: 학교에 가자마자 친구를 만났어요. As soon as I got to school, I met a friend. (immediately upon arrival)

  3. -고 나서: 학교에 가고 나서 친구를 만났어요. After going to school, I met a friend. (sometime after arriving)

Common Patterns

-자마자 emphasizes speed:

  • 문을 열자마자 고양이가 나갔어요. As soon as I opened the door, the cat went out.

-고 나서 emphasizes order and completion:

  • 샤워하고 나서 잠을 잤어요. After showering, I slept.

-을 때 for states and conditions:

  • 피곤할 때는 쉬어야 해요. When you're tired, you should rest.

More Examples

Using -을 때

  1. 한국어를 공부할 때 음악을 들어요. When I study Korean, I listen to music.

  2. 어제 집에 왔을 때 비가 왔어요. When I came home yesterday, it was raining.

  3. 시간이 없을 때는 택시를 타요. When I don't have time, I take a taxi.

Using -자마자

  1. 벨이 울리자마자 학생들이 나갔어요. As soon as the bell rang, the students left.

  2. 영화가 시작하자마자 잠들었어요. I fell asleep as soon as the movie started.

  3. 선물을 보자마자 좋아했어요. I liked it as soon as I saw the gift.

Using -고 나서

  1. 운동하고 나서 샤워해요. After exercising, I shower.

  2. 영화를 보고 나서 저녁을 먹었어요. After watching a movie, we ate dinner.

  3. 일이 끝나고 나서 연락할게요. I'll contact you after work is finished.

Practice

  1. Fill in the blank using -을 때: 날씨가 좋___ 공원에 가요.

  2. Connect using -자마자: 집에 도착하다 + 전화했어요.

  3. Connect using -고 나서: 청소하다 + 쉴 거예요.

  4. Choose the correct connector: The moment I heard it, I understood. a) 들을 때 b) 듣자마자 c) 듣고 나서

  5. Translate: When I was a child, I lived in Seoul. (어리다, 서울에 살다)

  6. Which emphasizes immediate succession?: 문을 열___ 들어왔어요. a) 열 때 b) 열자마자 c) 열고 나서

  7. Create a sentence with -을 때 showing simultaneous actions (요리하다, 노래를 부르다)

  8. Explain the difference:

  9. 밥을 먹을 때 전화했어요.
  10. 밥을 먹자마자 전화했어요.

  11. Translate using -고 나서: After thinking about it, I decided. (생각하다, 결정하다)

  12. Fix if wrong: 바쁘자마자 연락하세요. (If wrong, provide correct form)

Show Answers 1. 날씨가 좋**을 때** 공원에 가요. *When the weather is nice, I go to the park.* 2. 집에 도착하자마자 전화했어요. *As soon as I arrived home, I called.* 3. 청소하고 나서 쉴 거예요. *After cleaning, I'll rest.* 4. **b) 듣자마자** 이해했어요. *As soon as I heard it, I understood.* (Explanation: Immediate understanding requires -자마자) 5. 어렸을 때 서울에 살았어요. *When I was young, I lived in Seoul.* (Note: 어리다 → 어렸을 때 for past state) 6. **b) 열자마자** 들어왔어요. *As soon as I opened the door, I came in.* (Explanation: Immediate succession) 7. 요리할 때 노래를 불러요. *When I cook, I sing.* / *I sing while cooking.* 8. **Difference explanation**: - 밥을 먹을 때 전화했어요. = *Someone called while I was eating.* (During the meal, simultaneous) - 밥을 먹자마자 전화했어요. = *I called as soon as I finished eating.* (Immediately after eating) 9. 생각하고 나서 결정했어요. *After thinking about it, I decided.* 10. **Wrong!** -자마자 cannot be used with adjectives. **Correction**: 바쁠 때 연락하세요. *Contact me when you're busy.* Or if meaning "as soon as you become busy": 바빠지자마자 연락하세요. *Contact me as soon as you become busy.*