How do you pluralize irregular noun?

Answer 1

A regular plural is a noun to which an -s or an -es is added to form the plural. An irregular plural is plurals formed in some other way. There are many forms of irregular plural nouns.

• Nouns ending in the letter -o, sometimes they are pluralized by adding -s, while other words must be pluralized by adding es. These words must be memorized, because there is no simple rule to explain the differences. (echo, echoes or hero, heroes)
• Most nouns ending in o preceded by a vowel are pluralized by simply adding -s. (photo, photos or tattoo, tattoos)
• Some nouns ending in the letter -y, replace the ending y with -ies. (baby, babies or story, stories)
• Nouns ending in -ypreceeded by a vowel (a complex vowel sound), an -s is simply added, as usual. (day, days or turkey, turkeys)
• Some nouns ending in -f or -fe, replace the ending -f or -fe with -ves. (life, lives or knife, knives)
• Some nouns change the vowel sound in becoming plural. (man, men or goose, geese)
• Some plurals are left over from Old English; many plurals come from other languages. Examples of these irregular plural nouns are:

singular / plural

child / children

ox / oxen

cactus / cacti

alumnus / alumni

datum / data

medium / media

oasis / oases

basis / bases

larva / larvae

antenna /antennae

index / indeces

person / people