It could be an adjective :"The neigbouring areas" or a verb (a gerund): "The suburbia neighbouring the city".
adverb
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i want to know what part of speech is camping
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"City state" is a noun. It refers to a city that is also a separate sovereign state or political entity.
all of it
Rome is a proper noun. It names a specific city.
Recife is the name of a city so it is a proper noun
Cities is a common noun in plural. (The singular would be city.)
"Chicago" can be a noun (referring to a city) or an adjective (describing something related to the city).
The part of speech for "answer" is a noun.
part of speech
The part of speech for this particular word is a noun.
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what part of speech is work
adverb