A noun is a word that represents a person, place, thing, or idea.

Singular nouns refer to one item, while plural nouns refer to more than one item.

The plural form of 'foot' is 'feet'.

The plural form of 'elf' is 'elves'.

The plural form of 'letter' is 'letters'.

The plural form of 'man' is 'men'.

The plural form of 'wolf' is 'wolves'.

Most nouns form their plural by adding 's' or 'es' to the end.

Some exceptions include 'child' (children), 'mouse' (mice), and 'tooth' (teeth).

An irregular plural noun is a noun that does not follow the standard rules for pluralization.