orae gongbuhamyeon nuni apayo.

오래 means for a long time. It is an adverb, so it describes the action 공부하다 (to study).

In this sentence:

• 오래 공부하면 = if/when you study for a long time

A common beginner mistake is to think 오래 is an adjective, but here it is functioning adverbially.

You may also see 오랫동안, which also means for a long time. In many everyday situations, 오래 is a shorter, very natural choice.

공부하면 uses the grammar -면, which means if or when.

Breakdown:

• 공부하다 = to study
• 공부하면 = if/when (someone) studies

So:

• 오래 공부하면 눈이 아파요 = If/When you study for a long time, your eyes hurt

This structure is used to show a condition or a general result.

Compare:

• 공부해서 = because/and then studying
• 공부하면 = if/when studying

Here, -면 is the right choice because the sentence expresses a general cause-and-result relationship.

It can feel like if or when, depending on context.

In a sentence like this, it often has a general truth feeling:

• 오래 공부하면 눈이 아파요
  = If you study for a long time, your eyes hurt = When you study for a long time, your eyes hurt

In English, both translations can work. Korean -면 often covers both ideas when talking about regular results or common experiences.

This is a very common question.

In Korean, with adjectives/descriptive verbs like 아프다 (to hurt, to be painful), the body part often takes the subject marker 이/가, not the object marker 을/를.

So Korean says:

• 눈이 아파요 = the eyes hurt / my eyes hurt

Not:

• 눈을 아파요 ❌

Other similar examples:

• 머리가 아파요 = My head hurts.
• 배가 아파요 = My stomach hurts.
• 다리가 아파요 = My leg hurts.

English uses my very often, but Korean often leaves possession unstated when it is obvious.

Because Korean often omits things that are already understood from context.

If you say:

• 눈이 아파요

it usually naturally means:

• My eyes hurt

You can say 제 눈이 아파요 (my eyes hurt) if you want to be extra explicit, but in normal conversation it is usually unnecessary.

This is very common with body parts, family relationships, and other things that are obvious from the situation.

It can mean either eye or eyes, depending on context.

Korean nouns often do not mark plural unless it is necessary. So:

• 눈이 아파요 can mean my eye hurts or my eyes hurt

In this sentence, because studying for a long time usually affects both eyes, English often translates it as your eyes hurt or my eyes hurt.

Korean does have a plural marker -들, but you usually would not say 눈들이 아파요 here.

The subject is omitted, which is very normal in Korean.

Depending on context, this sentence can mean:

• If I study for a long time, my eyes hurt
• If you study for a long time, your eyes hurt
• If one studies for a long time, the eyes hurt

In practice, Korean often leaves pronouns out when they are obvious or unnecessary. So the sentence sounds natural even without I or you.

아파요 is the polite, non-formal form of 아프다.

Breakdown:

• dictionary form: 아프다
• polite form: 아파요

This style is very common in everyday conversation. It is polite and natural in most situations.

Compare:

• 눈이 아파요 = polite everyday speech
• 눈이 아픕니다 = more formal
• 눈이 아파 = casual, plain/informal speech

So this sentence is in a standard polite conversational style.

This happens because of Korean verb/adjective conjugation rules.

아프다 ends in ㅡ. When adding -아요/어요, the ㅡ often drops.

So:

• 아프다
• stem: 아프-
• drop ㅡ
• add -아요
• 아파요

This is the normal conjugation for 아프다.

A similar example:

• 바쁘다 → 바빠요
• 슬프다 → 슬퍼요 (slightly different vowel result, but also an ㅡ-stem pattern)

It is best understood as a noun + 하다 combination.

• 공부 = study / studying
• 하다 = to do

So literally, 공부하다 is to do study, but in natural English it means to study.

This pattern is very common in Korean:

• 운동하다 = to exercise
• 일하다 = to work
• 청소하다 = to clean
• 숙제하다 = to do homework

Because of this, the conjugation happens on 하다:

• 공부하면
• 공부해요
• 공부했어요

Yes, absolutely.

• 오래 공부하면 눈이 아파요
• 오랫동안 공부하면 눈이 아파요

Both are natural and both mean roughly If you study for a long time, your eyes hurt.

The difference is mostly style:

• 오래 = shorter, simple, very common
• 오랫동안 = a bit more explicit, like for a long period of time

In everyday Korean, 오래 is often enough.

The structure is:

• 오래 = for a long time
• 공부하면 = if/when (someone) studies
• 눈이 = eyes + subject marker
• 아파요 = hurt

So the overall pattern is:

time adverb + action + conditional + subject + descriptive verb

Very literally:

• For a long time study-if, eyes hurt

Natural English:

• If you study for a long time, your eyes hurt

Korean word order is often different from English, especially because the verb usually comes at the end.

It is most naturally understood as a general statement or a habitual result.

• 오래 공부하면 눈이 아파요
  = If/When you study for a long time, your eyes hurt

It does not strongly sound like a one-time event happening right this second. Instead, it sounds like a general truth or repeated experience.

If you wanted to emphasize right now, you might say something like:

• 오래 공부했더니 눈이 아파요
  = I studied for a long time, so now my eyes hurt

That version feels more connected to a specific situation.

In casual speech, you can say:

• 오래 공부하면 눈이 아파

This is the same sentence, just without the polite -요.

Compare:

• 오래 공부하면 눈이 아파요 = polite
• 오래 공부하면 눈이 아파 = casual

Use the casual form with close friends, people younger than you, or in informal situations. Use 아파요 in normal polite conversation.