Irregular Plurals of Nouns
Introduction
Although most nouns have plurals formed according to regular rules, some nouns have unusual, or irregular plurals.
Types of irregular plural
There are many types of irregular plural, but these are the most common:
| Noun type | Forming the plural | Example |
|---|---|---|
| Ends with -fe | Change f to v then Add -s |
knife ⇒ knives life ⇒ lives wife ⇒ wives |
| Ends with -f | Change f to v then Add -es |
half ⇒ halves wolf ⇒ wolves loaf ⇒ loaves |
| Ends with -o | Add -es | potato ⇒ potatoes tomato ⇒ tomatoes volcano ⇒ volcanoes |
| ends with -us | Change -us to -i | cactus ⇒ cacti nucleus ⇒ nuclei focus ⇒ foci |
| ends with -is | Change -is to -es | analysis ⇒ analyses crisis ⇒ crises thesis ⇒ theses |
| ends with -on | Change -on to -a | phenomenon ⇒ phenomena criterion ⇒ criteria |
| ALL KINDS | Change the vowel or Change the word or Add a different ending |
man ⇒ men foot ⇒ feet child ⇒ children person ⇒ people tooth ⇒ teeth mouse ⇒ mice |
| Unchanging | Singular and plural are the same |
sheep deer fish (sometimes) |
When you are sure that you understand the lesson, try to find the correct plurals.
mosquito
mosquitoes
CORRECT!!
mosquitoies
mosquitos
wolf
wolves
CORRECT!!
wolfes
wolfs
goose
geese
CORRECT!!
gooses
goosies
cactus
cacti
CORRECT!!
cactuses
cactuss
Adapted from source