Possible Duplicate:
“I'm not sure what the right way is”
Direct and indirect questions are not usually the same:
What is your name?
I don't know what your name is.
But sometimes, they become the same:
What is wrong with you?
I don't know what is wrong with you.What is available?
I like to know what is available.
So my question is, what the grammatical rule is when they become the same.
You seem to be very confused. Grammatically, "I don't know what your name is." and "I don't know what is wrong with you." are not questions. Of course, if I say, "I don't know xxx." in a situation where it is normal for somebody to tell me xxx, then the statement functions as a question, but that's a matter of context and usage, not grammar.
Simple statements:
I don't know what your name is, and I don't want to know either. I prefer anonymity.
I have run every medical test, and they are all negative. I cannot explain your symptoms. I don't know what is wrong with you.
Statements functioning as questions:
I'm sorry, but you have the advantage of me. I don't know what your name is.
I can't help you if you won't explain your problem. I don't know what is wrong with you.
