| Noun type
|
Forming the plural
|
Examples
|
| 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)
|
