May 14, 2022
뭘
[mweol]
(question marker) (informal) (almost never used; most of the time used only in order to clarify, to ask about an omitted object in a sentence) what
뭘 (informal) is the short form for 뭐를 [mweo·reul], which is also the short form for the formal 무엇을 [mu·eos·eul].
In colloquial speech, 뭐 will always be used instead, unless the speaker needs to clarify about the object of a verb.