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