Irregular plural forms
There are several irregularities in the plural forms of English nouns. These are known as irregular plurals.
Man / men
Woman / women
Fungus / fungi
Medium / media
Person / people
The plurals of some nouns are formed by changing letters within the word.
foot / feet
mouse / mice
goose / geese
Some words are always singular in usage.
ascites
herpes
Some words are always plural in usage.
adnexa
genitalia
Some words retain the same form, whether they are singular or plural.
media
series
forceps
scissors
facies
biceps, triceps, quadriceps
If you are uncertain about an irregular plural form, check a dictionary.
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