I say it's a verb
The word "brag" can be both a verb and a noun. As a verb, it is an action word that means to boast or talk with excessive pride. As a noun, it refers to an instance of bragging or boasting.
The part of speech for this particular word is a noun.
part of speech
The part of speech for "answer" is a noun.
what part of speech is beneath
adverb
The preposition for the word "boast" is "about" or "of." For example, you can boast about your achievements or boast of your accomplishments.
The part of speech for "explicit" is an adjective.
The part of speech for "lecturer" is a noun.
The part of speech for "rapid" is an adjective.
The part of speech of "came" is a verb.
The part of speech for "breezy" is an adjective.