Add -ly: fastidious - fastidiously.
Serenely is an adverb. The adjective form is serene.
The adjective is omnivorous and the adverb is omnivorously.
No, "familiar" is an adjective and does not have an adverb form.
No, it is not. It is an adverb, the adverb form of the adjective unsteady.
No, it is an adverb. It is the adverb form of the adjective perfect.
No, it is an adverb. It is the adverb form of the adjective contented.
The word skilfully is an adverb.The adjective form of the word is skilful.
It depends on the noun or adjective form. The adverb form of the adjective "active" is "actively."
Yes, it is. It is an adjective form of the noun conscience.
Nervous is an adjective. The adverb form is nervously.
No, it is an adjective. The adverb form is electrically.
No, it is not an adverb. Truthful is an adjective, and the adverb form is "truthfully."