Pamir Mountains vs mainland China

Pamir Mountains and mainland China both are nouns.

Word	Noun	Adjective	Verb	Adverb
Pamir Mountains	Yes	No	No	No
mainland China	Yes	No	No	No

Pamir Mountains (noun)	mainland China (noun)
a mountain range in central Asia that is centered in Tajikistan but extends into Kyrgyzstan and Afghanistan and Pakistan and western China	a communist nation that covers a vast territory in eastern Asia; the most populous country in the world