When to use surprise in Korean
Korean: 뜻밖[ tteus-bakk ]

When to use it
뜻밖 means something unexpected or surprising. You use it when something happens that you did not think would happen, like a guest, a gift, or a problem. It often comes before a noun, such as in "뜻밖의 선물," which means "an unexpected gift."
Example sentences
집에서 뜻밖의 손님이 왔어요.
An unexpected guest came to the house.
학교에서 뜻밖의 시험이 있었어요.
There was a surprise test at school.
공원에서 뜻밖의 비가 왔어요.
Unexpected rain came at the park.
친구가 뜻밖의 전화를 했어요.
My friend made a surprise phone call.
가게에서 뜻밖의 할인을 봤어요.
I saw an unexpected discount at the store.
여행 중에 뜻밖의 문제를 만났어요.
We had an unexpected problem during the trip.