seonsaengnim seolmyeongeul hyudaeponeuro nogeumhae dumyeon najunge bokseuphagi pyeonhaeyo.

If you record the teacher’s explanation on your phone, it’s convenient to review later.

Breakdown of seonsaengnim seolmyeongeul hyudaeponeuro nogeumhae dumyeon najunge bokseuphagi pyeonhaeyo.

• ~을: object particle
• 선생님: teacher
• 휴대폰: cell phone
• ~으로: instrumental particle

Questions & Answers about seonsaengnim seolmyeongeul hyudaeponeuro nogeumhae dumyeon najunge bokseuphagi pyeonhaeyo.

Why is it 선생님 설명 and not 선생님의 설명?

In Korean, the possessive marker 의 is often omitted when the relationship is obvious.

So 선생님 설명 literally looks like teacher explanation, but it naturally means the teacher’s explanation.

Both are possible:

• 선생님 설명 = natural, common
• 선생님의 설명 = also correct, a bit more explicit

In everyday speech, Korean often leaves out 의 when it is easy to understand from context.

Why does 설명 take 을 in this sentence?

Because 설명 is the thing being recorded.

The verb is 녹음하다 = to record, and the direct object of that verb is marked with 을/를:

• 설명을 녹음하다 = to record the explanation

So in this sentence:

• 선생님 설명을 = the teacher’s explanation as the object
• 녹음해 두면 = if you record it and keep it / have it recorded for later

What does 휴대폰으로 mean here?