사건이 · 사건을
incident, event, case (crime or legal)
Example
경찰이 그 사건을 아직 조사하고 있어요.
The police are still investigating that incident.
Word parts
사 matter, event+건 item, case
Literally 'matter item': a case to deal with.
Good to know
Pronounced [사껀]. 사건 is an incident, often criminal; 사고 is an accident like a car crash.
Related words