Seldom, rarely, infrequently
opposite is an adjective
The opposite of the adverb bitterly is sweetly.The word sweetly is also an adverb.
The adverb "well" is the usual opposite of the adverb "badly." If "badly" is used to mean "extremely or greatly" the opposite could be "slightly." E.g. He was badly bruised./He was slightly bruised.
No, it is an adjective, the opposite of definite. The adverb form is indefinitely.
Roughly
gently
Careful.
The opposite of the adverb firmly (securely) is loosely.*When used to mean forcefully or determinedly (e.g. firmly stated), the opposite could be gently, weakly, or waveringly.
Usually is an adverb of frequency.
No, it is not an adverb. The word violate is a noun (the opposite word, inviolate, is an adjective , as is violated).
Adverb does not actually have an antonym, but it might be an adjective: an adjective only modifies nouns and pronouns; an adverb modifies a verb, adjective, or another adverb.
The opposite of carefully is carelessly.Both carefully and carelessly are adverbs.