First & Second Declension Adjectives
Bonus, bona, bonum is the biggest adjective family in Latin — borrow the feminine endings from 1st-declension stella, the masculine from 2nd-declension servus, and the neuter from 2nd-declension bellum, and you can describe almost anything.
Sallust pairs them effortlessly: bonus et ignāvōs aequē sibi exoptant — "the good man and the worthless want the same things for themselves."
The forms are easy. The traps are at the edges. Pulcher and sacer keep the e in their stem (pulchra, sacra), but miser drops it (miserī, not misrī) — you only know which from the genitive.
And nine adjectives — sōlus, tōtus, ūnus, ūllus, nūllus, alius, alter, uter, neuter — break ranks in the singular: their genitive ends in -īus and their dative in -ī across all three genders. Verg.
Aen. x.442 nails the trap in one line: sōlus ego in Pallanta feror, sōlī mihi Pallās — "I alone go against Pallas; for me alone is Pallas."
Borrow the masculine and neuter from 2nd-decl. nouns and the feminine from 1st-decl. — same endings, no new memorization.
Pulcher-style adjectives keep the e (pulchra); niger-style drop it (nigra); the genitive feminine tells you which. Sōlus, tōtus, ūnus and the other six pronominals always take -īus / -ī in the singular.
| Case | SG. M. | SG. F. | SG. N. | PL. M. | PL. F. | PL. N. |
|---|---|---|---|---|---|---|
| Nom. | bon-us | bon-a | bon-um | bon-ī | bon-ae | bon-a |
| Gen. | bon-ī | bon-ae | bon-ī | bon-ōrum | bon-ārum | bon-ōrum |
| Dat. | bon-ō | bon-ae | bon-ō | bon-īs | bon-īs | bon-īs |
| Acc. | bon-um | bon-am | bon-um | bon-ōs | bon-ās | bon-a |
| Abl. | bon-ō | bon-ā | bon-ō | bon-īs | bon-īs | bon-īs |
| Voc. | bon-e | bon-a | bon-um | bon-ī | bon-ae | bon-a |
| Case | SG. M. | SG. F. | SG. N. | PL. M. | PL. F. | PL. N. |
|---|---|---|---|---|---|---|
| Nom. | pulcher | pulchr-a | pulchr-um | pulchr-ī | pulchr-ae | pulchr-a |
| Gen. | pulchr-ī | pulchr-ae | pulchr-ī | pulchr-ōrum | pulchr-ārum | pulchr-ōrum |
| Dat. | pulchr-ō | pulchr-ae | pulchr-ō | pulchr-īs | pulchr-īs | pulchr-īs |
| Acc. | pulchr-um | pulchr-am | pulchr-um | pulchr-ōs | pulchr-ās | pulchr-a |
| Abl. | pulchr-ō | pulchr-ā | pulchr-ō | pulchr-īs | pulchr-īs | pulchr-īs |
| Case | SG. M. | SG. F. | SG. N. | PL. M. | PL. F. | PL. N. |
|---|---|---|---|---|---|---|
| Nom. | miser | miser-a | miser-um | miser-ī | miser-ae | miser-a |
| Gen. | miser-ī | miser-ae | miser-ī | miser-ōrum | miser-ārum | miser-ōrum |
| Dat. | miser-ō | miser-ae | miser-ō | miser-īs | miser-īs | miser-īs |
| Acc. | miser-um | miser-am | miser-um | miser-ōs | miser-ās | miser-a |
| Abl. | miser-ō | miser-ā | miser-ō | miser-īs | miser-īs | miser-īs |
| Case | SG. M. | SG. F. | SG. N. | PL. M. | PL. F. | PL. N. |
|---|---|---|---|---|---|---|
| Nom. | sōl-us | sōl-a | sōl-um | sōl-ī | sōl-ae | sōl-a |
| Gen. | sōl-īus | sōl-īus | sōl-īus | sōl-ōrum | sōl-ārum | sōl-ōrum |
| Dat. | sōl-ī | sōl-ī | sōl-ī | sōl-īs | sōl-īs | sōl-īs |
| Acc. | sōl-um | sōl-am | sōl-um | sōl-ōs | sōl-ās | sōl-a |
| Abl. | sōl-ō | sōl-ā | sōl-ō | sōl-īs | sōl-īs | sōl-īs |
See It In Action
— Sall. Cat. 11.2
Bonus and ignāvus — both 1st/2nd-decl. adjectives — work as substantives ("the good man," "the worthless"). When the noun is obvious, the adjective alone carries it.
— Verg. Aen. x. 442
Vergil pairs sōlus (nom. m. sg., regular) with sōlī (dat. m. sg., the pronominal -ī). One line, both forms — the trap and its tell, side by side.
— Verg. Aen. i. 286
Pulchrā (abl. f. sg.) drops the e in the stem and takes the 1st-decl. -ā ending — and agrees across declensions with orīgine (3rd decl.). Agreement is by case, not by ending shape.
Render as "the X men" or "X people" — Latin drops the noun when the gender supplies it.
bonī = "good men" / "the good"; Rōmānī = "the Romans"
Render as "the X women" — gender alone supplies the noun.
bonae = "good women"; miserae = "wretched women"
Render as "X things" — abstract or collective.
bona = "good things, possessions"; vēra = "true things, the truth"
Render as the abstract concept — "the X" or "what is X".
bonum = "the good, a good thing"; pulchrum = "beauty" / "what is beautiful"
Both adjectives end in -er in the m. nom. sg. — but only one keeps the e in the rest of the paradigm. The genitive feminine reveals the truth.
e belongs to the stem — appears in every form
miser, misera, miserum
wretched (gen. f. miserae)
e is a nominative crutch — gone in oblique cases
pulcher, pulchra, pulchrum
beautiful (gen. f. pulchrae)
Tip: Look up the feminine in your dictionary entry. Asper, līber, miser, prosper, tener and -fer/-ger compounds keep the e. Almost everything else (niger, sacer, pulcher, integer, sinister, noster, vester) drops it.
In Vergil's line sōlī mihi Pallās ("for me alone, Pallas"), what case and number is sōlī?
Study Tips
- •Memorize bonus, bona, bonum cold — every other adjective in this family clones its endings, even the -er and pronominal types.
- •When you meet an -er adjective, look up its genitive feminine before declining: pulchra keeps the e, misera keeps it, but the consonant-cluster types like nigra, sacra, aegra drop it.
- •Drill the nine pronominal adjectives as a chant — sōlus, tōtus, ūllus, ūnus, ūnī, nūllus, alius, alter, neuter, uter. Genitive -īus, dative -ī, plural is regular bonus.