naeil achime hoeuiga isseoseo allameul miri matchwoyo.

I set the alarm in advance because I have a meeting tomorrow morning.

Breakdown of naeil achime hoeuiga isseoseo allameul miri matchwoyo.

• ~을: object particle
• 내일: tomorrow
• ~가: subject particle
• 있다: to have

Questions & Answers about naeil achime hoeuiga isseoseo allameul miri matchwoyo.

Why is there 에 in 내일 아침에?

에 marks a point in time when something happens.

• 아침에 = in the morning
• So 내일 아침에 means tomorrow morning

A useful detail: 내일 often appears without 에, but nouns like 아침, 점심, 저녁, 밤 commonly take 에 when they indicate time.

So:

• 내일 아침에 회의가 있어요 = There is a meeting tomorrow morning

Why is it 회의가 있다 and not 회의를 있다?

Because 있다 does not take a direct object. It expresses existence or having, so the thing that exists is marked with 이/가.

• 회의가 있다 = there is a meeting / I have a meeting
• not 회의를 있다

This is the same pattern as:

• 약속이 있어요 = I have an appointment
• 시험이 있어요 = There is a test / I have a test

So in this sentence, 회의가 is the natural form.

What does 있어서 mean here?