Seo Dong-chang:	의주야 Eui-joo!
Yeo Eui-joo:	어머 웬일이야? Oh! What are you doing here?
Seo Dong-chan:	저기 너한테 좀 부탁할게 있어서 Well, I have a favor to ask you.

웬일이야? (What are you doing here? / What’s up?)

웬 – what, for what reason
일 – matter, affair
이야? – casual question ending

Casual – 웬일이야?
Polite – 웬일이에요? / 웬일이세요?

>> an expression of surprise: depending on the context, it could mean “what brings you here?” or “what’s the occasion?”, “what’s up?” (i.e. when someone does something unusual or out of his or her character / when receiving an unexpected phone call etc.)

>> to emphasize your surprise at the person’s presence at a specific location, add [여긴] meaning “here” and say 여긴 웬일이야? / 웬일이야 여긴? (What are you doing HERE?)

>> make similar sentences using different adverbs such as [어쩐] or [무슨] to replace [웬]
ex. 여긴 어쩐일이세요?
무슨일이야 여긴?