Nouns ending in a consonant followed by -y change the -y to -ies in the plural form.
Possibility is regular. It follows the -ies Conversion rule.
Use plural verbs: "The possibilities are ready" (not "is ready").
Yes. The plural possibilities is standard across all English variants.
The word possibility follows the standard English pluralization rule. When forming the plural, possibility becomes possibilities. This follows the -ies Conversion pattern, which is one of the most common plural rules in English.
Understanding why possibility becomes possibilities helps with spelling and pronunciation. Nouns ending in a consonant followed by -y change the -y to -ies in the plural form.
When using possibilities in writing, remember that it functions as a plural noun in sentences. It pairs with plural verbs and pronouns. For example: "The possibilities are ready" (not "is ready"). This subject-verb agreement is essential for grammatical correctness.