Tianjin vs city

Tianjin and city both are nouns.

Word	Noun	Adjective	Verb	Adverb
Tianjin	Yes	No	No	No
city	Yes	No	No	No

Tianjin (noun)	city (noun)
a major industrial center in northeastern China on the Grand Canal near the Yellow Sea; 3rd largest city in China	people living in a large densely populated municipality
	a large and densely populated urban area; may include several independent administrative districts
	an incorporated administrative district established by state charter