gapjagi iri saenggyeoseo yaksogeul chwisohaesseoyo.

In this sentence, 일이 생기다 is a very common expression meaning something came up or something happened.

• 일 can mean work, matter, issue, or something to deal with
• 생기다 literally means to occur, to come into being, or to arise

So 갑자기 일이 생겨서 does not mean something like a job was born. It means:

• because something suddenly came up
• because an unexpected matter arose

This is a very natural Korean excuse or explanation.

생겨서 is the contracted, natural form of 생기어서.

The verb is 생기다. When you attach -어서/-아서, Korean often contracts the form in everyday speech:

• 생기어서 → 생겨서

This kind of contraction is very common and sounds much more natural.

Here, -아서/-어서 means because or so.

So:

• 갑자기 일이 생겨서 = because something suddenly came up
• 약속을 취소했어요 = I canceled the appointment/plan

Together, the sentence means that the first part is the reason for the second part.

Important nuance:

• In many situations, -아서/-어서 can mean simple sequence, like and then
• But here, it clearly gives a reason: because something came up, I canceled the appointment

This is a very common Korean pattern.

In a sentence with a connective ending like -아서/-어서, the tense is often shown only in the final verb.

So even though 생겨서 looks non-past on its own, the whole sentence is understood in the past because the final verb is 취소했어요.

You can think of it like this:

• 갑자기 일이 생겨서 약속을 취소했어요
• Something came up suddenly, so I canceled the plan

Korean does not always mark tense separately on every verb in a connected sentence.

This is a great question because English often uses appointment or reservation in overlapping ways, but Korean separates them more clearly.

• 약속 = a promise, arrangement, or plan to meet someone
• 예약 = a reservation or booking, such as for a hotel, restaurant, doctor, or ticket

So in this sentence, 약속을 취소했어요 usually means:

• I canceled my plans
• I canceled an appointment/meeting with someone

If you were talking about canceling a restaurant booking, 예약을 취소했어요 would be more natural.

을/를 marks the direct object of the verb.

Here:

• 약속 = the plan/appointment
• 취소하다 = to cancel

So 약속을 취소하다 means to cancel the appointment/plan.

The thing being canceled is the object, so it takes 을.

갑자기 literally means suddenly or all of a sudden, but in sentences like this it often helps give the nuance of unexpectedly.

So 갑자기 일이 생겨서 feels like:

• because something unexpectedly came up
• because something came up out of nowhere

It helps make the explanation sound natural and believable.

Korean often omits the subject when it is obvious from context.

In 약속을 취소했어요, the implied subject is usually I:

• (제가) 약속을 취소했어요 = I canceled the appointment

But depending on context, it could also be we or another understood subject. Korean does this very often, especially in conversation.

They are similar, but not exactly the same.

• 약속을 취소했어요 = I canceled the appointment/plan
• 안 갔어요 = I didn't go

If you say 취소했어요, it means the plan itself was canceled, usually in advance or at least as a deliberate action.

If you say 안 갔어요, it only means you did not go. It does not necessarily mean you informed the other person or formally canceled anything.

So 취소했어요 is more appropriate when talking about canceling a planned meeting.

Yes. 취소했어요 is in the -어요 polite style, which is common and natural in everyday conversation.

Levels you could compare:

• 취소했어 = casual, used with close friends
• 취소했어요 = polite, everyday standard
• 취소했습니다 = more formal

So this sentence is polite but not overly formal.

Yes, very common.

일이 생기다 is one of the most natural ways in Korean to say:

• something came up
• I had something unexpected to deal with

Because it is somewhat vague, it is often used when the speaker does not want to explain the full reason in detail. That makes it sound natural, polite, and flexible.

For example, Koreans often say things like:

• 갑자기 일이 생겼어요.
• 개인적인 일이 생겨서요.
• 급한 일이 생겨서 못 갔어요.

All of these are very common in real life.