I'm guessing this MUST have been asked here before, but I can't find anything on it. If there's a relevant link please let me know.
An example of this is:
(When it comes to my hair, even though it was thick and lush last night, maybe since I haven't showered yet (?), it's wet and sticky this morning.)
I know question phrases can be used as nouns (e.g. 彼が何を買ったかを聞く), but like the example above I've also seen them used as adverbs. Up until now I chalked that up to loose and casual speech, but the above example is a JLPT sample test question, and so would not be particularly loose and casual.
What's the exact translation of a question phrase used as an adverb, and when is it or is it not appropriate?