In questions, these words indicate the thing you want to know, like English wh-words. In non-questions, they make reference to something indefinite, like any, some, some kind, etc. They can alos mean no, neither, or none when combined with negators like 없다, 않다, 아니다. (In a question) - 어느 = which. 어느 것이 좋아? = Which is good? - 어떤 = 어떠한 = what kind of. 어떤 일을 하고 싶어? = What kind of work would you like to do? - 뭐 = 무엇 = what (pronoun - the part you want to know). 뭐를 먹을까? = What should we eat? - 무슨 = what (adjective - requires a noun after it). 무슨 뜻이야? = (lit.) What meaning is it? => What does it mean? (in a statement) - 어느 (a certain, one, none). 어느 날 충격적인 소식을 들었다 = I heard a devastating piece of news one day. - 어떤 (some, some kind of, no). 어떤 일도 쉽지는 않다 = No task is easy per se. - 뭐 (what, whatever - pronoun). 네가 뭐라고 해도 상관 없다 = It doesn't matter whatever you might say. - 무슨 (what, whatever - adjective). 무슨 일이 있어도 오늘 떠나야 한다 = We must depart today no matter what (lit. "no matter what matter/event happens").