Could you tell me what the difference nominal WH clause and nominal relative clause is ? For example, nominal WH clause : no one knows what caused the accident. Nominal Relative clause: You call him whatever you want. How can I distinguish between the two. Another thing is the function of this sentence : [What I need most is a good rest] S. So , does the whole sentence function as a subject. That's what I have read. Thank you
In "You call him whatever you want" the "whatever you want" is a noun phrase consisting of a relative clause -- there is no noun head. Similarly, in "What I need most is a good rest" the subject noun phrase "what I need most" is a relative clause with no head noun.
However, in "No one knows what caused the accident", there is no relative clause. Instead, "what caused the accident" is an indirect question. "What caused the accident? Nobody knows."