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