A singular noun refers to one of something (a chair, a hat, a dog); a plural noun means more than one (chairs, hats, dogs).
In most cases we make a plural noun by adding s to a singular noun (car > cars).
Words that end in -ch, x, s or s-like sounds take -es for the plural (kiss > kisses).
When a noun ends in y we replace it with –ies to make the plural (city > cities).
There are also a lot of irregular nouns which do not follow the above rules, so it's a case of you having to learn them one by one!
Test your knowledge of irregular plural nouns with this quiz. Do you know the plural form of these nouns? Choose the correct plural form: