The word 'endangered is not a noun.
The word 'endangered' is the past participle, past tense of the verb to endanger. The past participle of the verb also functions as an adjective.
The noun form of the verb to endanger is endangerment.
The noun 'endangerment' is a common noun, a general word for any instance of putting someone or something at risk.
"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
"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?
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.