Plural forms

Nouns are mainly changed into plural form by taking s at the end. Look at the examples below:

Year                     Years

Gift                      Gifts

Boy                       Boys

School                  Schools

Hour                    Hours

Nouns that end in S, SH, CH, Z and X, need "es" instead of "s" to change into plural. Look at the examples below:

Kiss                     Kisses

Dish                    Dishes

Watch                Watches

Box                     Boxes

Bus                     Buses

When a nouns ends in "y" we have to change y to i and add es to the end of the word to change it to plural. Unless the letter before the y is a vowel(a, e, i, o and u) which in this case y doesn't change and s should be added. Look at the examples below:

Baby          Lady          City

Babies       Ladies       Cities

But...

Boy                Guy               Toy

Boys               Guys              Toys

Some more examples....

Monkey        Donkey          Key

Monkeys       Donkeys         Keys

When a noun ends in f or fe, to change the word to plural, F or fe changes to v and es should be added. Look at the examples below:

Wolf              Wolves

Self                Selves

Shelf              Shelves

Leaf               Leaves

Wife              Wives

Knife            Knives

There are some words in English that do not take s to change into plural form. Below are some examples:

Man                         Men

Woman                    Women

Foot                         Feet

Tooth                       Teeth

Child                       Children

For more information visit http://learnenglish.britishcouncil.org/en/english-grammar