Korean grammar '-아서/어서/여서(해서)'

 

1. Explanation

 : '-아서/어서/여서(해서)' indicates that the preceding clause(phrase, sentence) is the reason or the way for the following clause(phrase, sentence). It can be conjugated with the verb stem or adjective stem. And they take different particles and conjugations depending on their verb stems or adjective stems. You can translate '-아서/어서/여서(해서)' as 'because'. Let's look at the rules together. 

 

  (1) If the verb stem or adjective stem has vowel 'ㅏ or ㅗ',

      you have to conjugate it with '-아서'

  (2) If the verb stem or adjective stem has except vowel 'ㅏ or ㅗ',

      you have to conjugate it with '-어서'

  (3) The form '-하다.' changes to '-해서.'

     * '하-' conjugates with '-여서'. => '하여서' => '하여' can be contracted to '해' => '해서.'

 

  *Tip : How to make past tense

    1) Step 1 - Cheak the verb stem or adjective stem 

    2) Step 2 - Cheak the ending syllable's vowel 

    3) Step 3 - Conjugate with the correct one

 

 

*Source : National Institute of Korean Language

 

2. Examples

 비가 와서 늦었어요. (I was late because it was raining.)

 *오다 to come

  1) A verb stem is '오-'

  2) It has a vowel 'ㅗ'

  3) It conjugates with '-아서'

  4) 오아서

  5) '오아' can be contracted to '와'

  6) 와서

 

 컴튜터를 사서 돈이 없어요. (I don't have money because I bought a computer.)

 *사다 to buy 

  1) A verb stem is '사-'

  2) It has a vowel 'ㅏ'

  3) It conjugates with '-아서'

  4) 사아서

  5) '사아' can be contracted to '사'

  6) 사서 

 

 수업이 끝나서 집에 가요. (I'm going home because the class was over.)

 *끝나다 to be over

  1) A verb stem is '끝나-'

  2) It has a vowel 'ㅏ'

  3) It conjugates with '-아서'

  4) 끝나아서

  5) '나아' can be contracted to '나'

  6) 끝나서

 

 창문을 열어서 추워요. (It's cold because I opened the window.)

 *열다 to open

  1) A verb stem is '열-'

  2) It has a vowel 'ㅕ'

  3) It conjugates with '-어서'

  4) 열어서

   

 떡국을 먹어서 배가 불러요. (I'm full because I ate tteokguk.)

 *먹다 to eat

  1) A verb stem is '먹-'

  2) It has a vowel 'ㅓ'

  3) It conjugates with '-어서'

  4) 먹어서

 

 약속에 늦어서 미안해요. (I'm sorry because I was late for a plan.)

 *늦다 to be late

  1) A verb stem is '늦-'

  2) It has a vowel 'ㅡ'

  3) It conjugates with '-어서'

  4) 늦어서

 

 심심해서 전화했어요. (I called because I was bored.)

 *심심하다 bored 

  1) A form of the word is '-하다.'

  2) '-하다.' changes to '-해서'

  3) 심심해서

 

 궁금해서 물어봤어요. (I asked because I was curious.)

 *궁금하다 curious

  1) A form of the word is '-하다.'

  2) '-하다.' changes to '-해서'

  3) 궁금해서

 

 *I wrote in the past tense when I combined two sentences to make it more natural

 

3. Practice

 I'm sad because the concert was postponed.

 콘서트가 ____________ 슬퍼요. ( *연기되다 to be postpone / *연기하다 to postpone ) 

 

 I'm happy because I smile.

 ____________ 행복해요. ( *웃다 to smile ) 

 

 I'm busy because I started studying German.

 독일어 공부를 _____________ 바빠요. ( *시작하다 to start )

 

 I took a walk because the weather was nice.

 날씨가 _____________ 산책했어요. ( *좋다 nice )

 

 I will sleep late because I'm tired.

 _____________ 늦게까지 잤어요. ( *피곤하다 tired )

 

 It's quiet because I closed all doors and windows.

 모든 문과 창문을 _____________ 조용해요. ( *닫다 to close )

 

 Thank you because you helped me.

 _____________ 고마워요. ( *도와주다 to help )

 

 I will arrive early because I ride a bicycle.

 자전거를 _____________ 빨리 도착할 거예요. ( *타다 to ride )

 

4. Vocabulary

 비 rain / 오다 to come, fall / 늦다 late / 컴퓨터 computer / 사다 to buy / 돈 money / 없다 don't have / 수업 class / 끝나다 to be over / 집 house / 가다 to go / 창문 window / 열다 to open / 춥다 cold / 떡국 tteokguk / 먹다 to eat / 배부르다 to be full / 약속 plan / 늦다 late / 미안하다 sorry / 심심하다 bored / 전화하다 to call / 궁금하다 curious / 물어보다 to ask / 콘서트 concert / 연기되다 to be postponed / 슬프다 sad / 웃다 smile / 행복하다 happy / 독일어 German / 공부 studying / 시작하다 to start / 바쁘다 busy / 날씨 weather / 좋다 fine, nice / 산책하다 to take a walk / 피곤하다 tired / 자다 to sleep / 모든 all / 문 door / 닫다 to close / 조용하다 quiet / 도와주다 to help / 고맙다 to thank / 자전거 bicycle / 타다 to ride / 빨리 early / 도착하다 to arrive

 

5. Answer

  연기되어서 / 웃어서 / 시작해서 / 좋아서 / 피곤해서 / 닫아서 / 도와줘서(주어서) / 타서