There is none, kind is an adjective. Only nouns can be plural.
The plural for for the noun kind is kinds. How many kinds of candy to you sell?
Bags is the plural of bag, so bags is a plural noun.
Bags is the plural of bag, so bags is a plural noun.
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A. plural possessive
Pronouns like "they," "their," and "them" should be used with plural nouns.
"Quilts" is a plural noun.
concrete, plural
The plural of "a kind of antelope" is spelled gazelles.
The noun 'rockets' is a plural, common, concrete noun, the plural form for rocket; a word for a thing.
The plural series refers to a group of items or objects that are more than one and of the same kind. For example, "apples" would be the plural series of "apple."
The word kindness is the abstract noun form for the adjective kind.