Difference between fear and big problem in Korean

두려움·큰일이다.

fear — 두려움fear
Fear (두려움) is the feeling you have when something makes you scared or worried. You can use it to talk about fear in many situations, like darkness, tests, travel, or new experiences. In Korean, it is often used with verbs like “feel,” “have,” or “become smaller.”
How to say fear

big problem — 큰일이다.big problem
큰일이다 means "this is a big problem" or "oh no." People say it when something bad happens or when they are worried about trouble. You can use it in many daily situations, like being late, losing something, or forgetting homework.
How to say big problem

The difference

두려움 is the feeling of being afraid. 큰일이다 is the situation itself: something is wrong or may cause trouble.