Simple adverbs only contain one word. They can modify verbs,
adjectives, or other adverbs. Consider the following sentence:
Because Mark was not known to be an
extremely fast runner, everyone cheered quite excitedly
when he finished 1st place in the cross country race.
The first adverb, "extremely",
is modifying the adjective "fast" (here, “fast” is acting as an
adjective and is modifying the noun “runner”). It is answering the question,
“To what degree?”
The second adverb, "quite",
is modifying another adverb, "excitedly". It is also answering the
question, “To what degree?”
The last adverb in the sentence, "excitedly", is
modifying the verb, "cheered". It is answering the question, “In what
way?”