Rules regarding the formation of plurals
In English, we form the plurals of nouns by adding –s to the singular. Examples are given
below.
Boy -> boys
Girl -> girls
Book -> books
There are several exceptions to this rule. Nouns ending in –s, -sh, -ch and –x, form their
plurals by adding –es to the singular.
Examples are:
Box -> boxes
Class -> classes
Branch -> branches
Brush -> brushes
Watch -> watches
Most nouns ending in –o, generally form their plurals by adding –es.
Examples are:
Mango -> mangoes
Hero -> heroes
Potato -> potatoes
Volcano -> volcanoes
Some singular nouns ending in –o, form their plurals by simply adding –s.
Examples are:
Piano -> pianos
Photo -> photos
Stereo -> stereos
Dynamo -> dynamos
Nouns ending in a consonant + -y, form their plurals by changing that –y into –i and adding
–es.
Baby -> babies
Lady -> ladies
City -> cities
Story -> stories
Most nouns ending in –f or –fe form their plurals by changing –f or –fe into v and adding –es.
Leaf -> leaves
Life -> lives
Thief -> thieves
Knife -> knives
There are several exceptions to this rule and the following nouns form their plurals by simply
adding –s.
Examples
Roof -> roofs
Proof -> proofs
Dwarf -> dwarfs
Belief -> beliefs
A few nouns form their plurals irregularly. Examples are given below.
Man -> men
Woman -> women
Tooth -> teeth
Mouse -> mice
Some nouns have the singular and the plural alike. Examples are: swine, sheep, deer
The nouns dozen, score, pair, hundred and thousand do not have a plural form when they are
used after a number.
The car cost me five thousand dollars. (NOT … five thousands dollars)