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 |
-ī |
-ae |
-ī |
| Dative |
-ō |
-ae |
-ō |
| Accusative |
-um |
-am |
-um |
| Vocative |
-e |
-a |
-um |
| Ablative |
-ō |
-ā |
-ō |
Plural
| Case |
Masculine |
Feminine |
Neuter |
| Nominative |
-ī |
-ae |
-a |
| Genitive |
-ōrum |
-ārum |
-ōrum |
| Dative |
-īs |
-īs |
-īs |
| Accusative |
-ōs |
-ās |
-a |
| Vocative |
-ī |
-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 |