It might be good
to understand the difference between an adverb and an
adverbial construction. Let's have a look at these phrases:
a) He runs fast.
b) It is a fast car.
In a) fast is an adverb and in b) it is an adjective.
In a) it refers to the verb (and therefore has to be
an adverb), in b) it refers to a noun (and therefore
can only be an adjective).
a) He runs slowly.
b) It is a slow car.
Here we see the difference more clearly, -ly is the
English ending for adverbs (even though not all adverbs
do use this ending).
He does it well.
He does it with
She works smilingly.
She works with
We talk pleasantly.
We talk with
Well, smilingly and pleasantly
are adverbs, with great
care, with a smile and with pleasure are adverbial
constructions that havethe function
of an adverb in these sentences, but can have other functions, too.