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