Yap.Town

에 불이

a fire/light in …

→ 에
phrase Rare #20,363
a fire/light in … 에 marks the location, and 불 can mean either “fire” or “light,” depending on the context.
KO: 방에 불이 켜져 있어요.
EN: The light is on in the room.

깃발에 불이 붙었다.

The flag was set on fire.