There are 9 parts of speech or word classes in English language:
– nouns
– pronouns
– determiners
– verbs
– prepositions
– adjectives
– adverbs
– conjunctions
– interjections

We use adverbs to explain or describe:
– verbs,
– adjectives,
– other adverbs.

John speaks loudly.
– speak = verb
– loudly = adverb
– Adverb ‘loudly’ describes the verb ‘speaks.’

Mary lives there.
– lives = verb
– there = adverb
– Adverb ‘there’ describes the verb ‘lives.’

I saw John yesterday.
– saw = verb
– yesterday = adverb
– Adverb ‘yesterday’ describes the verb ‘saw.’

Jane is really beautiful.
– beautiful = adjective
– really = adverb
– Adverb ‘really’ describes the adjective ‘beautiful.’

She drives incredibly slowly.
– drives = verb
– slowly = adverb
– incredibly = adverb
– Adverb ‘slowly’ describes the verb ‘drives.’
– Adverb ‘incredibly’ describes the adverb ‘slowly.’

We use comparative adverbs to:
– compare how an action is done by two people
Joe ran fast, but Mary ran faster.
faster = comparative adverb

– express changes in actions
She began to walk more quickly.
more quickly = comparative adverb

How to Form Comparative Adverbs

(1) two-syllable adverbs or more

more + adverb

quickly -> more quickly
slowly -> more slowly
happily -> more happily
seriously -> more seriously
efficiently -> more efficiently

(2) one-syllable adverbs:

Adverb + -er

fast -> faster
hard -> harder
high -> higher

(3) Irregular adverbs

well -> better
badly -> worse
early -> earlier

(4) We DO NOT use ‘more’ with one-syllable adverb and irregular adverbs.

talk quickly (correct)
talk more quickly (correct)
ran faster (correct)
ran more faster (wrong)
study better (correct)
study more better (wrong)