Latin plurals

Latin declension is the patterns according to which Latin words are declined, or have their endings altered to show grammatical case and gender. Nouns, pronouns, and adjectives are declined (verbs are conjugated), and a given pattern is called a declension. There are five declensions, which are numbered and grouped by ending and grammatical gender. For simple declension paradigms, visit the Wiktionary appendices: , , , , . Each noun follows one of the five declensions, but some irregular nouns have exceptions.

Adjectives are of two kinds: those like 'good' belong to the first and second declensions, using first-declension endings for the feminine, and second-declension for masculine and neuter. Other adjectives such as belong to the third declension. There are no fourth- or fifth-declension adjectives.

Pronouns are also of two kinds, the personal pronouns such as 'I' and 'you (sg.)', which have their own irregular declension, and the third-person pronouns such as 'this' and 'that' which can generally be used either as pronouns or adjectivally. These latter decline in a similar way to the first and second noun declensions, but there are differences; for example the genitive singular ends in -īus or -ius instead of -ī or -ae.

The cardinal numbers 'one', 'two', and 'three' also have their own declensions (ūnus has genitive -īus like a pronoun), and there are also numeral adjectives such as 'a pair, two each', which decline like ordinary adjectives.

A complete Latin noun declension consists of up to seven grammatical cases: nominative, vocative, accusative, genitive, dative, ablative and locative. However, the locative is limited to few nouns: generally names of cities, small islands and a few other words.

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