Q: Where are adverbials found in the clause?
A: Adverbials are words, phrases, or clauses that are generally found in the predicate of a clause.
I couldn't sleep last night because my neighbors hosted a very loud party.
Q: Are adverbials ever found in the subject of the clause?
A: Although adverbials "belong" in the predicate, they are frequently moved to the beginning of an entire clause and are placed before the subject of that clause. When this happens, they are always separated from the subject of the clause by a comma.
Because my neighbors hosted a very loud party last night, I couldn't sleep.
Q: Is there a difference between adverbs and adverbials?
A: Adverbs are single words that describe when, where, why, or how things happen. Adverbials are words, phrases, or clauses that do the same. In other words, "adverbs" fall under the larger category of "adverbials." The adverbials in these two sentences are written in red.
Rosa sang loudly. Yesterday, she sang in the auditorium.