sueop jeone gwajereul jechulhaeya haeyo.

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Questions & Answers about sueop jeone gwajereul jechulhaeya haeyo.

Why is 수업 전에 used to mean before class? What does 전에 do here?

전에 is a time particle that attaches to a noun to mean “before (noun).”

  • 수업 (class) + 전에 = 수업 전에 (“before class”).
  • It turns 수업 into an adverbial phrase indicating when something happens.
  • You can likewise use 후에 (“after”) as in 수업 후에 = “after class.”
What does 과제 mean and why is it followed by in 과제를 제출해야 해요?

과제 means “assignment” or “homework.”

  • The particle marks it as the direct object of the verb.
  • In Korean, objects generally need 을/를 to show what’s being acted upon.
  • So 과제를 tells us “the assignment” is what you must submit.
What does the structure ~아/어야 해요 express? How do I form it correctly?

The pattern ~아/어야 해요 expresses obligation (“must” or “have to”).
Formation steps:

  1. Take the verb stem (drop -다 from the dictionary form).
  2. If the last vowel of the stem is ㅏ or ㅗ, add -아야 해요; otherwise add -어야 해요.
    • 제출하다 → stem 제출하-제출하 + 아야 해요 = 제출해야 해요.
  3. This literally means “it’s necessary to submit.”
Can I use ~아/어야 돼요 instead of ~아/어야 해요? Are they the same?

Yes. Both express “have to”:

  • ~아/어야 해요 comes from 하다 (“to do”).
  • ~아/어야 돼요 comes from 되다 (“to become”).
    They’re largely interchangeable in speech.
  • 해야 해요 is slightly more neutral/polite.
  • 해야 돼요 can feel a bit more casual.
Could I say 과제를 내야 해요 instead of 과제를 제출해야 해요? What’s the difference between 내다 and 제출하다?

Yes, you can say 과제를 내야 해요.

  • 내다 means “to turn in” or “to hand in” and is common in everyday contexts.
  • 제출하다 is more formal/offical (“to submit”).
    In most classroom conversations, they’re used interchangeably.
Why is the verb 제출해야 해요 at the end of the sentence? Can I move it earlier?

Korean follows Subject-Object-Verb (SOV) order, so the verb always ends the clause.
You can shuffle time and object phrases before that—for example:

  • 수업 전에 과제를 제출해야 해요.
  • 과제를 수업 전에 제출해야 해요.
    But the verb phrase 제출해야 해요 stays at the very end.
What level of politeness is -해야 해요? How would I make it more or less formal?

-해야 해요 is polite (해요체), suitable for everyday situations (e.g., teacher–student, coworkers).

  • More formal (합니다체): 수업 전에 과제를 제출해야 합니다.
  • Less formal/casual (해체): 수업 전에 과제를 제출해야 해.