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