run, walk, jog
The verb form of "fast" is "to fast." It means to refrain from eating food for a period of time, usually for religious, health, or personal reasons.
Fast is an adjective.It can be used to describe people/objects/animals.That car is fast!I can run really fast!Cheetahs move fast!---Fast as a verb means to abstain from food or drink, usually for religious reasons.
"being briskly" = is not a verb - "briskly" means at a fast pace.
"to fast" means to refrain from eating (possibly only some some foods), so, for example, "Catholics sometimes fast during Lent".
The verb is talks.
it is used to describe a verb usually after the verb or sometimes before it for example: He runs fast. Fast is the adverb that describes the verb, runs.
Ran is the verb in that sentence>
The future tense of the verb form of "fast" is will fast.
adhere is a verb and means: to stick fast to a surface or substance believe in and follow the traditions/practices of (e.g. religion)
The monk was told to fast before mattins. The cheetah ran too fast for him to catch.
Only in unusual constructions, where it modifies a verb or adjective and means very or only:"We had to leave but fast.""The repair took but a minute.
"Fast" can be both an action verb and an adjective. As an action verb, it indicates the act of moving quickly. As an adjective, it describes something that is quick or speedy.