ADVERB.
Adverbs are added to Verbs and Adjectives to denote some modification or circumstance of an action or quality: as, the manner, order, time, place, distance, motion, relation, quantity, quality, comparison, doubt, affirmation, negation, demonstration, interrogation.
In English they admit of no Variation; except some few of them, which have the degrees of Comparison: as,[40] “often, oftener, oftenest;” “soon, sooner, soonest.”
An Adverb is sometimes joined to another Adverb to modify or qualify its meaning; as, “very much; much too little; not very prudently.”