Latin Adjectives: First and Second Declension

Word Endings

First and second declension adjectives follow the basic -us, -a, -um pattern, the same as how first and second declension nouns are declined. Always remember that these endings should always follow the root, which is obtained by taking the genitive singular and removing the ending. This rule will help you with more complex words like sacer.

Singular

Case Masculine Feminine Neuter
Nominative -us -a -um
Genitive -ae
Dative -ae
Accusative -um -am -um
Vocative -e -a -um
Ablative

Plural

Case Masculine Feminine Neuter
Nominative -ae -a
Genitive -ōrum -ārum -ōrum
Dative -īs -īs -īs
Accusative -ōs -ās -a
Vocative -ae -a
Ablative -īs -īs -īs

Examples:

bonus, -a, -um (good)

Singular

Case Masculine Feminine Neuter
nom. bonus bona bonum
gen. bonī bonae bonī
dat. bonō bonae bonō
acc. bonum bonam bonum
voc. bone bona bonum
abl. bonō bonā bonō

Plural

Case Masculine Feminine Neuter
nom. bonī bonae bona
gen. bonōrum bonārum bonōrum
dat. bonīs bonīs bonīs
acc. bonōs bonās bona
voc. bonī bonae bona
abl. bonīs bonīs bonīs

sacer, sacra, sacrum (sacred)

Singular

Case Masculine Feminine Neuter
nom. sacer sacra sacrum
gen. sacrī sacrae sacrī
dat. sacrō sacrae sacrō
acc. sacrum sacram sacrum
voc. sacre sacra sacrum
abl. sacrō sacrā sacrō

Plural

Case Masculine Feminine Neuter
nom. sacrī sacrae sacra
gen. sacrōrum sacrārum sacrōrum
dat. sacrīs sacrīs sacrīs
acc. sacrōs sacrās sacra
voc. sacrī sacrae sacra
abl. sacrīs sacrīs sacrīs

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