どんな

どんな asks what kind of thing something is, and it always comes right before a noun: どんな音楽が好きですか, "what kind of music do you like?"; 新しい先生はどんな人ですか, "what's the new teacher like?"

It belongs to the こんな・そんな・あんな・どんな family: こんな本 is "a book like this", そんな事 "that sort of thing".

Compare its neighbours:

• どの picks one from a known set: どの本? "which book?"
• どう stands alone before です: どうですか, "how is it?"
• どんな describes the kind: どんな本? "what sort of book?"