When the final -y is preceded by a consonant, change the -y to -i and add -es:

baby–>babies
lady–>ladies

If a noun ends in -fe or -f, the ending is changed to -ves (except: beliefs, chiefs, roofs, staffs).

life–>lives
thief–>thieves

Add -es to nouns ending in -sh, -ch, -s, -z, and -x. (Exceptions: monarchs, stomachs.)

wish–>wishes
class–>classes

Both the -s and -es spellings are accepted for nouns ending in -o.

tomato–>tomatoes
hero–>heroes

The plural form of these nouns is also irregular.

child–>children
foot–>feet
goose–>geese
man–>men
tooth–>teeth

The plural is the same as the singular for these nouns.

deer–>deer
fish–>fish
sheep–>sheep
species–>species

The final sound of these plurals is pronounced like the word sees.

crisis–>crises
thesis–>theses

Examples of Irregular Noun Plurals

• You can also drop off the car at any of our agencies nationwide.
• All children must go to school.