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Breakdown of meoriga apaseo sukjereul mos haeyo.
하다hada
to do
~을~eul
object particle
~가~ga
subject particle
숙제sukje
homework
못mos
cannot
~어서~eoseo
so
아프다apeuda
painful
머리meori
head
Questions & Answers about meoriga apaseo sukjereul mos haeyo.
Why do Koreans say 머리가 아프다 (literally the head hurts) to mean I have a headache?
The pattern for expressing pain in Korean is body part + 이/가 + 아프다. It literally says "the head is painful," but it functions just like I have a headache. In everyday speech, people use 머리가 아프다 rather than more formal or medical expressions like 두통이 있다.
What is the function of -아서 in 아파서?
The ending -아서 (or -어서 after vowel stems) is a conjunctive ending that links two clauses by expressing a cause or reason—equivalent to because in English. Attaching it to the adjective stem 아프- gives 아파서, meaning because (I) am in pain, which leads into the result clause 숙제를 못 해요.
Why is it 숙제를 못 해요 and not 숙제를 안 해요?
못 하다 means cannot do (an inability or external condition prevents the action), whereas 안 하다 means do not do (a deliberate choice). Here, the speaker isn’t choosing to skip homework—they physically can’t because of a headache—so 못 해요 is the correct expression of inability.
Could the speaker use the past tense 못 했어요 instead of 못 해요?
No, because 못 해요 describes a present inability: I can’t (right now) do my homework. Using 못 했어요 (past tense) would mean I couldn’t do it (in the past), which breaks the link to a currently ongoing headache.
Is the object marker -을/를 with 숙제 mandatory? Can we say 숙제 못 해요?
In casual speech, particles are often dropped, so 숙제 못 해요 is understandable. However, in standard or polite Korean you should include the object marker: 숙제를 못 해요, to clearly mark 숙제 as the direct object.
Can you use other connectors like -니까 or -기 때문에 instead of -아서?
Yes. All three express causation but differ in tone and formality:
• 아프니까 숙제를 못 해요 — slightly more formal/neutral than -아서.
• 아프기 때문에 숙제를 못 해요 — more formal or written style, emphasizes the cause.
• 아파서 — common in spoken, colloquial style.
Could you also express the same idea with 할 수 없다 instead of 못 하다?
Yes. You can say:
머리가 아파서 숙제를 할 수 없어요.
Here 할 수 없다 (“cannot do”) is more explicit/formal, but the overall meaning—I can’t do my homework because my head hurts—remains the same.
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Korean has multiple speech levels that indicate formality and politeness. The most common are the formal polite (‑습니다/‑ㅂ니다), informal polite (‑아요/‑어요), and casual (‑아/‑어) forms. Which level you use depends on who you're speaking to and the social context.
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