There is no word in English spelled 'sity'.
The noun city, is a common noun, a general word for a place with a concentrated population; a word for any city anywhere.
A proper noun is the name of a specific person, place, or thing. A proper noun form the common noun 'city' is the name of a city, for example, Rome, Sydney, or Tulsa, OK.
A city is a common noun.
"Park Avenue" is a proper noun, because it is a place. Proper nouns like this should always be capitalized.
Common
It is a proper noun, because it is the name of a specific thing.
proper
Proper noun
Pencil proper or common noun
it's a common noun. a proper noun would be Spider-Man.
Proper noun or common noun
The noun cassette is a common noun.
a common noun?
The answer is proper noun. Examples of common noun and proper noun are: Proper noun: Mary Collins Common noun: monkey
Camel is a common noun.