Adverb of Manner

English
Adverbs of manner are the most common and they are easy to recognize because they end with -ly.
Mary sings beautifuly.


Spanish
Most adverbs of manner can be recognized by the ending -mente which corresponds to the English ending -ly.
fácilmente = easily
naturalmente = naturally
rápidamente = rapidly

IMPORTANT
Adverbs unlike adjectives never change their forms.  In Spanish adjectives have to agree in gender and number with the noun they modify.  This is not so with adverbs.
The tall girl talked rapidly.
La chica alta habló rápidamente.

The tall boy talked rapidly.
El chico alto habló rápidamente
Remember in English good is an adjective and well is an adverb.  In Spanish bueno is the adjective meaning good and bien is the adverb meaning well.
The student writes good English.
good modifies the noun English.

The student writes well.
well modifies the verb writes.

The good students speak Spanish well.
Los estudiantes buenos hablan español bien.
buenos is the adjective for the noun estudiantes (students)
bien is the adverb for the verb hablan (speak)
Note: buenos is the plural of bueno because there are more than one student, but bien did not change form.