Adverbs can act as modifiers of a verb, an adjective, another adverb or a whole sentence.
Adverbs are invariable: that is, they do not vary according to the gender, number or person of the word they are modifying.
Adverbs in -mente
In Portuguese, many adverbs are formed by adding the suffix -mente (‘-ly’) to the adjective.
But adjectives ending in -o in the masculine singular change to the feminine singular before the suffix -mente is added:
lento > lenta lentamente = slow slowly
Adverbs in -mente have no accents, even if the adjective from which they are formed does:
bfácil, facilmente = easy, easily
When two or more adverbs are used in the same sentence, only the last one takes the suffix -mente:
Usually adverbs are placed before the adjective or after the verb they modify
Ela chorou desesperadamente. She cried desperately.
Adverbs of time and place can either precede or follow the verb they modify
Ele chegou hoje. He arrived today.
Adverbs of negation always precede the verb
Ela nunca tinha feito isso. She had never done that.