This is the 2335th most frequent Japanese word.
なんで
"なんで" means "why" or "how come."
In this sentence, 'なんで' is used to ask for the reason or cause for the action of someone's presence.
なんで君がここにいるの？
Why are you here?
Here, 'なんで' is used to inquire about the reason behind someone's emotional state.
彼はなんで怒っているのか分からない。
I don't understand why he is angry.
'なんで' in this sentence is utilized to question the necessity or the reasoning behind an obligation.