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