cave vs roof

cave and roof both are nouns.

Word	Noun	Adjective	Verb	Adverb
cave	Yes	No	Yes	No
roof	Yes	No	Yes	No

cave (noun)	roof (noun)
a geological formation consisting of an underground enclosure with access from the surface of the ground or from the sea	a protective covering that covers or forms the top of a building
	protective covering on top of a motor vehicle
	an upper limit on what is allowed
	the inner top surface of a covered area or hollow space

cave (verb)	roof (verb)
explore natural caves	provide a building with a roof; cover a building with a roof
hollow out as if making a cave or opening