게 뭔지 알아

know what … is

→ 것+이
phrase Rare #24,727
know what … is Used to ask whether someone knows what something is or what an action is like. The phrase before 게 identifies the thing or action.
KO: 내가 배운 게 뭔지 알아?
EN: Do you know what I learned?

내가 배운 게 뭔지 알아?

Do you know what I learned?

— 증오 (1995)

진짜 무서운 게 뭔지 알아?

You know what's really scary?

— 장화, 홍련 (2003)

방금 읽은 게 뭔지 알아?

Do you know what I just read?

— 그을린 사랑 (2010)