Most nouns ending in -o add -es to form the plural (with some exceptions like photo/photos).
Intro is regular. It follows the -es Addition rule.
Use plural verbs: "The introes are ready" (not "is ready").
Yes. The plural introes is standard across all English variants.
The word intro follows the standard English pluralization rule. When forming the plural, intro becomes introes. This follows the -es Addition pattern, which is one of the most common plural rules in English.
Understanding why intro becomes introes helps with spelling and pronunciation. Most nouns ending in -o add -es to form the plural (with some exceptions like photo/photos).
When using introes in writing, remember that it functions as a plural noun in sentences. It pairs with plural verbs and pronouns. For example: "The introes are ready" (not "is ready"). This subject-verb agreement is essential for grammatical correctness.