pluralizing

Pluralizing is the process by which nouns and sometimes pronouns, adjectives, and verbs mark or reflect plurality. In many languages, number is a grammatical category that indicates how many entities are being referred to. Plural forms can be created by adding affixes, modifying the stem, or by using separate words or numerals.

In English, plural forms are usually created by adding -s or -es: cat -> cats, bus -> buses. Some nouns form their plurals with a change to the stem: man -> men, woman -> women; some involve spelling changes: leaf -> leaves, loaf -> loaves; there are many irregular plurals: child -> children, foot -> feet, mouse -> mice, goose -> geese. A small number of nouns have the same form in singular and plural (sheep, deer, series, species). Some words are pluralia tantum, used only in plural form.

Other languages use varied patterns: German often adds -e or -er and may umlaut the stem (Kind -> Kinder; Mann -> Männer). Russian marks plurals with suffixes -ы or -и; Arabic has sound plurals formed with fixed suffixes or more complex broken plurals. Hebrew uses -im or -ot for masculine and feminine plurals, respectively. In many languages, pluralization also affects adjectives and verbs in agreement within a noun phrase.

In linguistics and natural language processing, pluralization rules are described as morphology and are implemented in rules or lexicons; some systems model irregulars and language-specific patterns. Pluralization is thus a common aspect of grammar, interlinking with syntax, semantics, and typology.