The plural forms of most English nouns are made by adding –s to the singular form. “Forms” and “nouns” from the previous sentence are perfect examples. However, many commonly-used English nouns have irregular plural forms. Some of these nouns follow alternate pluralization rules. Other nouns are identical in both singular and plural forms. Still other nouns have completely unique singular and plural forms.

 

–F/–FE to –VES

Nouns ending in –f or –fe preceded by consonant or a single vowel change to –ves in the plural:

 

Singular	Plural
calf	calves
dwarf	dwarves
hoof	hooves
knife	knives
leaf	leaves
life	lives
self	selves
thief	thieves
wife	wives
wolf	wolves

 

If a noun ending in –f /–fe is preceded by two consecutive vowels, just add –s:

 

Singular	Plural
chief	chiefs
proof	proofs
spoof	spoofs

 

 

­–O to –OES

Some nouns ending in –o change to –oes in their plural forms while other simply take –s. Here are several commonly-used examples of each.

 

–O to –OES
Singular	Plural
domino	dominoes
echo	echoes
hero	heroes
mosquito	mosquitoes
potato	potatoes
tomato	tomatoes
zero	zeroes

 

–O to –OS
Singular	Plural
embryo	embryos
patio	patios
solo	solos
studio	studios
zoo	zoos

 

Some –o words can take either ­–o or –oes in the plural:

 

–O to –OS or –OES
Singular	Plural
cargo	cargo(e)s
flamingo	flamingo(e)s
halo	halo(e)s
tornado	tornado(e)s
volcano	volcano(e)s

 

Note: Nouns with a vowel before the final –o always take –s in the plural.

 

 

Nouns Ending in –CH, –S, –SH, –X, or –Z

When a noun ends in –ch, –s, –sh, –c, or –z, add –es to form the plural:

 

Singular	Plural
bus	buses
church	churches
fox	foxes

 

Note: Nouns where the –ch is pronounced as a “K” are an exception to this rule. To form the plural of these nouns, just add –s. For example, the plural of “stomach” is “stomachs.”

 

–Y to –IES

Nouns ending in a consonant plus –y drop the ­–y and add –ies in the plural form:

 

Singular	Plural
activity	activities
daisy	daises
family	families

 

 

Changing Vowel Sounds

Several English nouns change vowel sounds in their plural forms. Commonly-used vowel changing nouns include:

 

Singular	Plural
foot	feet
goose	geese
mouse	mice
(wo)man	(wo)men
tooth	teeth

 

 

Identical Singular and Plural

Finally, some nouns (especially the names of animals) do not change from the singular to the plural:

 

Singular	Plural
deer	deer
fish	fish
sheep	sheep

 

That’s all for this lesson. Next time we’ll look at words with foreign origins that have retained their plural forms from their original languages.