Joao Pessoa vs metropolis

Joao Pessoa and metropolis both are nouns.

Word	Noun	Adjective	Verb	Adverb
Joao Pessoa	Yes	No	No	No
metropolis	Yes	No	No	No

Joao Pessoa (noun)	metropolis (noun)
a city in northeastern Brazil near the Atlantic Ocean to the north of Recife	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts