Quote:
Originally Posted by uptheirons
Seems like A and B are asking subtly different questions. The "what" can be omitted in A but not B.
Not even subtle, I would think.
What, are you crazy? = What? Are you crazy? = What did you just say? And doesn't that make you sound crazy?
What are you, crazy? = What are you? Crazy? = What's wrong with you? Is it that you are crazy?
Since both are possible, this seems to argue for the value of punctuation as a guide to meaning. (Spoken, they would sound different.)