Complex sentences that contain a noun clause

The dependent clause in these sentences functions as a noun (NC), that is:

• As subjects (S) or objects (O) of verbs (V)

What she said (S) was (V) right.

I didn’t understand (V) what he said (O).

• As complements of non-finite verbs (NFV)

They wanted to know (NFV) whether they should go (NC).

• As objects of prepositions (P)

He was not responsible for (P) what happened later (NC).