Adverb: an ADjective acting as a VERB (or relating to the verb as opposed to the noun).
Soft (adjective): The soft bunny was sleeping. [The bunny was soft]
Softly (adverb): I pet the bunny softly. [The pet was soft]
Happy (adjective): The happy boy grinned. [The boy was happy]
Happily (adverb): The boy smiled happily. [The smile was happy]
Shut up, I'm working on my grammar skills. Bleh to you all.