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