oneul ane bogoseoreul kkeutnaeya haeyo.

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Questions & Answers about oneul ane bogoseoreul kkeutnaeya haeyo.

What does 오늘 안에 mean exactly, and how is it different from 오늘까지?

오늘 안에 means within today—i.e., at some point before the day ends (before midnight in most contexts). It emphasizes the time window.

  • 오늘 안에 끝내야 해요 = You must finish it sometime during today.

오늘까지 means by today (as a deadline) and often implies no later than today (today is the last acceptable day). It emphasizes the deadline.

  • 오늘까지 끝내야 해요 = You must finish it by today (today is the cutoff).

They’re often similar in real life, but 안에 feels more like “within the bounds of,” and 까지 feels more like “up to / until (deadline).”


Why is there no object particle like 를/을 after 보고서?

Korean often drops particles when the meaning is clear, especially in casual or neutral speech. The full form could be:

  • 오늘 안에 보고서를 끝내야 해요.

But 보고서를보고서 is a common omission. Keeping can sound a bit more explicit/clear or slightly more formal, but both are natural.


What does -아/어야 해요 mean, and how strong is it?

-아/어야 해요 expresses necessity/obligation: must / have to / need to.

  • 끝내야 해요 = (I/you/we) have to finish.

Strength-wise, it’s a clear obligation, but 해요 keeps it polite. If you want it softer, you might use:

  • 끝내야 할 것 같아요 = It seems we have to / I think we need to finish. Or if you want it stronger:
  • 끝내야 합니다 = must finish (formal)
  • 끝내야 돼요 = must finish (more direct, common in speech)

How is 끝내다 different from 끝나다?
  • 끝내다 is transitive: to finish something (you actively complete it).
    • 보고서를 끝내다 = to finish the report
  • 끝나다 is intransitive: to be finished / to end (it ends on its own).
    • 회의가 끝나다 = the meeting ends

So in this sentence, 보고서를 끝내야 해요 is correct because the report is something you finish.


Why do we use 끝내야 해요 instead of 끝내야 돼요 or 끝내야 합니다?

All three are correct; they differ in politeness/style:

  • 끝내야 해요: polite, neutral, widely usable
  • 끝내야 돼요: very common in conversation; can sound a bit more blunt/insistent
  • 끝내야 합니다: formal (presentations, official messages, work reports)

The sentence you have is a good default polite style.


Who is the subject—I, you, or we? It doesn’t say.

Korean often omits the subject if context makes it clear. 끝내야 해요 can mean:

  • I have to finish (it)
  • You have to finish (it)
  • We have to finish (it)

Context (who’s responsible, who you’re talking to) determines it. If you want to specify:

  • 제가 오늘 안에 보고서를 끝내야 해요 = I have to finish it today.
  • 당신이/너가 오늘 안에 보고서를 끝내야 해요 = You have to finish it today. (often avoided; sounds direct)
  • 우리가 오늘 안에 보고서를 끝내야 해요 = We have to finish it today.

What is the role of 안에 grammatically—what does it attach to?

안에 literally means inside (of) and is used with time expressions to mean within a time period.

  • 오늘 안에 = inside today → within today Other examples:
  • 3일 안에 = within 3 days
  • 한 시간 안에 = within an hour

So 안에 attaches to a time period and sets the deadline window.


Is the word order fixed? Could I say 보고서를 오늘 안에 끝내야 해요?

Yes, that’s also natural. Korean word order is flexible as long as the grammar is clear:

  • 오늘 안에 보고서를 끝내야 해요 (time first)
  • 보고서를 오늘 안에 끝내야 해요 (object first; can emphasize the report)
  • 보고서는 오늘 안에 끝내야 해요 (topic-marked; “As for the report…”)

Why is it 보고서 and not 보고서가?

보고서가 would make the report the grammatical subject, which usually doesn’t fit with 끝내다 (since 끝내다 takes an object). You could say:

  • 보고서가 오늘 안에 끝나야 해요 = The report has to be finished within today.
    Here you switch to 끝나다 (intransitive), so 보고서가 works.

But with 끝내다, the report is what you finish → object (보고서를).


How would I make this sentence more formal or more casual?

More formal:

  • 오늘 안에 보고서를 끝내야 합니다.
  • 금일 내로 보고서를 완료해야 합니다. (very formal/businessy)

More casual:

  • 오늘 안에 보고서 끝내야 해.
  • 오늘 안에 보고서 끝내야 돼.

What is the nuance of 끝내야 해요 compared to 끝내고 말 거예요?
  • 끝내야 해요 = obligation/necessity (must; required)
  • 끝내고 말 거예요 = determination (“I’m going to finish it no matter what”)

So 끝내야 해요 is about requirement, while 끝내고 말 거예요 is about strong will.


How is this pronounced in natural speech? Any common contractions?

Common natural pronunciation changes:

  • 끝내야 해요 often sounds like 끈내야 해요 (tensing effect can be heard)
  • 해야 해요 is frequently heard closer to 해야 해요해야 해요/해야 해여 (fast speech variation), though spelling stays the same If using 돼요, in fast speech 해야 돼요 can sound like 해야 돼요해야 돼요 (shortened rhythm), but again spelling stays.

A careful, standard reading: 오늘 아네 보고서를 끈내야 해요 (approximate romanized sound).