KOREAN LEVEL UP › Korean grammar › -아/어서 (이유)
Korean Grammar “-아/어서 (이유)”: How to Use It (TOPIK 2)
How to attach it
Attach the pattern to the verb stem, which is the dictionary form without 다. Compare how each verb below changes depending on its last sound.
| Dictionary form | Meaning | With this pattern | Romanization |
|---|---|---|---|
| 보다 | to see, to watch | 봐서 | bwaseo |
| 읽다 | to read | 읽어서 | ilgeoseo |
| 하다 | to do | 해서 | haeseo |
| 열다 | to open | 열어서 | yeoreoseo |
What changes
- -아/어 follows the last vowel of the stem: 아 after ㅏ or ㅗ, 어 after other vowels (읽 → 읽어, 열 → 열어). When the stem ends in a vowel, the two vowels merge (보 + 아 → 봐), and 하다 becomes 해.
Explanation
길이 많이 막혀서 약속에 늦었어요.
“-아/어서” is a connecting ending that gives a reason: the first clause is the cause of the result that follows. The sentence means “The road was very congested, so I was late for the appointment.” Do not put the past marker -았/었- before it, and the second clause cannot be a command or suggestion.
Pronouncing the example sentence
Example sentence: 길이 많이 막혀서 약속에 늦었어요.
Said aloud, it sounds like [기리 마니 마켜서 약쏘게 느저써요].
| Syllable | Letters (consonant + vowel + final) | Romanization |
|---|---|---|
| 길이 | ||
| 길 | ㄱ+ㅣ+ㄹ | [기] gi |
| 이 | ㅇ+ㅣ | [리] ri |
| 많이 | ||
| 많 | ㅁ+ㅏ+ㄶ | [마] ma |
| 이 | ㅇ+ㅣ | [니] ni |
| 막혀서 | ||
| 막 | ㅁ+ㅏ+ㄱ | [마] ma |
| 혀 | ㅎ+ㅕ | [켜] kyeo |
| 서 | ㅅ+ㅓ | seo |
| 약속에 | ||
| 약 | ㅇ+ㅑ+ㄱ | yak |
| 속 | ㅅ+ㅗ+ㄱ | [쏘] so |
| 에 | ㅇ+ㅔ | [게] ge |
| 늦었어요 | ||
| 늦 | ㄴ+ㅡ+ㅈ | [느] neu |
| 었 | ㅇ+ㅓ+ㅆ | [저] jeo |
| 어 | ㅇ+ㅓ | [써] sseo |
| 요 | ㅇ+ㅛ | yo |
A ㅇ at the start of a syllable is silent; at the end of a syllable it sounds like “ng”.
Sound changes in this phrase
- Linking: when a syllable ending in a consonant (patchim) is followed by a syllable that starts with a vowel, the consonant moves over to the next syllable. 길이 → [기리]
- Silent ㅎ: a final ㅎ (including the ㅎ inside ㄶ and ㅀ) is not pronounced before a vowel. 많이 → [마니]
- Aspiration: ㅎ next to ㄱ, ㄷ, ㅂ or ㅈ blends with it into ㅋ, ㅌ, ㅍ or ㅊ. 막혀 → [마켜]
- Tensing: after a final ㄱ, ㄷ or ㅂ sound, ㄱ, ㄷ, ㅂ, ㅅ and ㅈ become tense (ㄲ, ㄸ, ㅃ, ㅆ, ㅉ). 약속에 → [약쏘게]
Politeness level of the example
Ends in -요. The everyday polite style, and a safe choice with shop staff, colleagues, strangers and anyone older than you.
Words in the example sentence
These words from the TOPIK vocabulary lists appear in the phrase (shown in dictionary form).
| Korean | Part of speech | Meaning | Level |
|---|---|---|---|
| 길 | noun | road, way | TOPIK level 1 |
| 막히다 | verb | to be blocked, to be congested | TOPIK level 3 |
Practice
Test yourself before you move on. Tap an answer.
Question 1 Choose the word that fits the blank: 길이 많이 막혀____ 약속에 늦었어요.
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Answer: 길이 많이 막혀서 약속에 늦었어요.
Question 2 Which is the correct form of 읽다 + -아/어서 (이유)?
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Answer: 읽어서
Question 3 Which is the correct form of 하다 + -아/어서 (이유)?
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Answer: 해서
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