The plural noun for a ball used to play Basketball is basketballs.
The noun 'basketball' as a word for the game or sport is a non-count noun.
The plural form of basket is baskets.
Singular. Plural is: they are, have and do.
Derogatory is an adjective, and has no plural forms.
There are two accepted forms of the noun: adviser and advisor.The plural forms are advisers and advisors.
The plural forms of the noun executrix are executrices or executrixes, both forms are accepted.
Plural possessive forms are used to show that more than one person or thing owns or is associated with something. For regular plural nouns, you add an apostrophe after the s (e.g., students' books). For irregular plural nouns that do not end in s, you add 's (e.g., children's toys).
basketballs
The plural form of basket is baskets.
There are two accepted forms of the noun: adviser and advisor.The plural forms are advisers and advisors.The plural possessive forms are advisers' and advisors'.
Singular.
plural forms are uteri or uteruses.
Verbs don't have plural forms.
There are two accepted plural forms of the noun vertex: vertices and vertexes.The plural possessive forms are vertices' and vertexes'.
Singular
The plural form of thesaurus is "thesauruses" or "thesauri."
Typically you would remove the plural suffix (-s, -es) or change it to the singular form (-y to -ies, -ies to -y) depending on the word. For irregular plurals, there may be specific rules to follow or you may need to consult a dictionary for the singular form.
The plural forms for the singular lumen is lumina or lumens, both are accepted plural forms.