Adverbial clauses are typically those that serve, in the manner of simple adverbs, to specify when, why, how etc. the action of a verb takes place. They are normally introduced by subordinating conjunctions such as 'when', 'because' or 'although'.
Occasionally, however, a structurally nominal (noun-like) clause can serve an adverbial function, as the underlined part of
I was wondering what to do.
(generally analysed as elliptical prepositional phrases, i.e. with the nominal clause as the object of a suppressed preposition:
I was wondering about what to do.)
Such clauses, however, might well be labelled 'adverbial noun clauses'.
- For Teachers