NUMBER

NUMBER is a grammatical category that tells the listener if a noun is one thing or more-than-one things.
 * Singular: An enemy is in the villiage.
 * Plural: Enemies are in the villiage.

(Please note: By tradition, all grammatical categories are written in CAPITAL letters.)

NUMBER should not be confused with the similar yet different concepts of numerals and quantifiers.

Characteristics
NUMBER is a grammatical category associated with nouns. The grammatical category NUMBER has two possible options: Some other languages have more options, but in English, a noun is either singular or plural.
 * Singular
 * Plural

Regular Rules
If a noun is plural and it ends in a 'y', then the 'y' is replaced by an '-ies'. e.g. fairy -> fairies

If a noun is plural and it does not end in a 'y', the suffix -s is added to the end of the word. e.g. dog -> dogs

These rule works for most nouns.

Irregular Nouns
There are some exceptions to the regular rule. Here are some examples where the irregular word is written in bold.