Korean grammar · TOPIK 2

Because - the speaker's own reason (-(으)니까): Korean Grammar with Examples

Everything you need to use because - the speaker's own reason (-(으)니까) correctly: the patterns, when to use them, examples with audio, common mistakes and exercises with answers.

Quick answer

-(으)니까 gives a reason as the speaker sees it. Unlike -아서/어서, it can be used with commands and suggestions, and it can carry the past tense. Key patterns: Because..., so...; Stem ending in a consonant + 으니까; Because it had..., with the past tense.

Patterns

FormStructureExample
Vowel stem + 니까Because..., so...바쁘니까 나중에 전화할게요.
I am busy, so I will call you later.
Consonant stem + 으니까Stem ending in a consonant + 으니까위험하니까 조심하세요.
It is dangerous, so please be careful.
Past tense + 으니까/-니까V + 았/었으니까
Because it had..., with the past tense
비가 왔으니까 길이 미끄러워요.
It rained, so the road is slippery.

How to use Because - the speaker's own reason (-(으)니까)

1. Reason + command

Only -(으)니까 can come before a command

춥니까 창문을 닫으세요.
It is cold, so please close the window.

2. Reason + suggestion

Used before a suggestion (-(으)ㄹ까요?, -(으)ㅂ시다)

배고프니까 밥을 먹을까요?
We are hungry, so shall we eat?

3. The speaker's own reason

Gives the reason as the speaker sees it

피곤하니까 오늘은 쉴 거예요.
I am tired, so I am going to rest today.

Key words

왜냐하면 (because)그러니까 (so, that is why)그래서 (so, therefore)

Tips and common mistakes

Because - the speaker's own reason (-(으)니까): exercises with answers

Pick the right option, then open the answer to check it.

1. Fill in the reason ending before a command: 아프다 (to hurt): 몸이 아프___ 병원에 가세요.

Options: 고 · 니까 · 아서 · 지만

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니까. Reason before a command takes -(으)니까: 아프니까 병원에 가세요 means 'you are ill, so go to the hospital'.

2. Fill in the reason ending: 늦다 (to be late): 지금 늦었___ 빨리 가야 해요.

Options: 니까 · 어니까 · 어서 · 으니까

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으니까. 늦었으니까 means "because it is already late" (past 었 + 으니까). -아서/어서 can never follow the past tense, so 늦었어서 is wrong. The sentence means "We are late, so we have to hurry."

3. Choose the correct sentence: 'It is raining, so let's take a taxi.'

Options: 비가 오고 택시를 탑시다. · 비가 오니까 택시를 탑시다. · 비가 오으니까 택시를 탑시다. · 비가 와서 택시를 탑시다.

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비가 오니까 택시를 탑시다.. Reason before a suggestion takes -(으)니까: -아서/어서 cannot come before 탑시다.

4. Choose the correct sentence: 'It is dangerous, so please do not come closer.'

Options: 위험하고 가까이 오지 마세요. · 위험하니까 가까이 오지 마세요. · 위험하으니까 가까이 오지 마세요. · 위험해서 가까이 오지 마세요.

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위험하니까 가까이 오지 마세요.. Reason before a polite prohibition takes -(으)니까: 위험하니까 오지 마세요. -아서 cannot come before 마세요.

5. Tell them apart: choose the WRONG one - -아서/어서 cannot be used here:

Options: 늦었으니까 서두릅시다. · 배고파서 같이 밥 먹읍시다. · 배고프니까 같이 밥 먹읍시다. · 비가 오니까 우산을 가져오세요.

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배고파서 같이 밥 먹읍시다.. -아서/어서 cannot precede a suggestion in -읍시다. The correct form is 배고프니까 같이 밥 먹읍시다.

6. Put 춥다 (ㅂ-irregular) + (으)니까: 날씨가 ___ 따뜻하게 입으세요.

Options: 추우니까 · 추워니까 · 춥니까 · 춥으니까

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추우니까. 춥다: ㅂ becomes 우 before 으, giving 추우니까. A reason followed by a request takes -(으)니까. The sentence means "It is cold, so dress warmly."

7. Reason + suggestion: 없다: 시간이 없___ 택시를 탑시다.

Options: 고 · 니까 · 어서 · 으니까

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으니까. 없다: the stem ends in a consonant, so 으니까. -아서/어서 cannot come before a suggestion (-ㅂ시다). The sentence means "We do not have time, so let's take a taxi."

8. Past-tense reason + (으)니까: 밥을 다 ___ 이제 나갈까요?

Options: 먹어었으니까 · 먹었니까 · 먹었어서 · 먹었으니까

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먹었으니까. Past 었 + 으니까 gives 먹었으니까 (-(으)니까 can follow the past tense, -아서 cannot). The sentence means "We have finished eating, so shall we go out now?"

9. Put 멀다 (stem ending in ㄹ) + (으)니까: 학교가 ___ 버스를 타세요.

Options: 머니까 · 멀니까 · 멀어니까 · 멀으니까

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머니까. 멀다: the stem ends in ㄹ, which drops before ㄴ, giving 머니까. The sentence means "The school is far, so take the bus."

10. Noun + (이)니까: 오늘은 토요일___ 늦게 일어나도 돼요.

Options: 니까 · 으니까 · 이니까 · 이으니까

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이니까. 토요일 ends in the consonant ㄹ, so it takes 이니까. The sentence means "Today is Saturday, so it is fine to get up late."

11. Reason + command: 비가 오다: 비가 ___ 우산을 가져가세요.

Options: 오니까 · 오으니까 · 와서 · 왔어서

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오니까. A reason followed by a command (-(으)세요) needs -(으)니까, not -아서/어서. 오다 ends in a vowel, so 오니까. The sentence means "It is raining, so take an umbrella."

12. Choose the correct sentence: 'This food is spicy, so eat it slowly.'

Options: 이 음식은 매우니까 천천히 드세요. · 이 음식은 매워니까 천천히 드세요. · 이 음식은 매워서 천천히 드세요. · 이 음식은 맵으니까 천천히 드세요.

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이 음식은 매우니까 천천히 드세요.. 맵다: ㅂ becomes 우, giving 매우니까. Because a command follows, 매워서 cannot be used. The sentence means "This food is spicy, so please eat slowly."

13. Choose the ungrammatical sentence:

Options: 늦어서 빨리 갑시다. · 늦었으니까 빨리 갑시다. · 바쁘니까 다음에 만나요. · 추우니까 문을 닫으세요.

Show answer

늦어서 빨리 갑시다.. -아서/어서 cannot come before a suggestion (-ㅂ시다). The correct form is 늦었으니까 빨리 갑시다 ("We are late, so let's hurry").

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