The word police is a common noun, a word for any police.
A common noun can become a proper noun if it is used for the name of a specific person, place, thing, or a title, such as the New York City Police Department or the movies 'Police Academy' and 'Police Academy 2'.
Police is a common noun. Proper nouns name a specific police officer or a specific police department. Examples: Officer Glen Martin The Glendale Police Department
Government is a common noun. Proper nouns are the unique names of people, places, or things. Common nouns are the words for general things. If a common noun is part of a name, it becomes a proper noun. Pronouns always replace proper and common nouns.
"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
it's a common noun. a proper noun would be Spider-Man.
Pencil proper or common noun
Proper noun or common noun
The noun cassette is a common noun.
a common noun?