Adverbs are, of course adverbials, but not all adverbials are adverbs.
Match the term in italics to the definition.
He left by bus.
He left at six o'clock.
He left slowly.
He left earlier.
He left last August.
He left through that door.
He left sobbing loudly.
He left when he saw me.
He left because he need to catch a train.
He left to get his train.
adverbial - noun time phrase
adverbial - time clause
adverbial clause - reason
adverbial - prepositional manner phrase
adverb - manner
adverbial - non-finite (participial) clause
adverb - time
adverbial prepositional place phrase
adverbial - infinitive of purpose
adverbial - prepositional time phrase