* Quietly is an adverb, meaning in a quiet manner.
* Adverbs of manner don't typically form comparatives and superlatives in the same way as adjectives.
Instead of using comparative and superlative forms, we use other adverbs to express different degrees of quietness:
* More quietly - This is used to show a greater degree of quietness.
* Most quietly - This is used to show the highest degree of quietness.
Example:
* Quietly: She walked quietly down the hallway.
* More quietly: He walked more quietly than she did.
* Most quietly: Of all the students, she walked most quietly.