| Nom. | duo | duae | duo |
| Gen. | duōrum | duārum | duōrum |
| Dat. | duōbus | duābus | duōbus |
| Acc. | duōs, duo | duās | duo |
| Abl. | duōbus | duābus | duōbus |
a. So ambō, both, except that its final o is long.
3. Trēs is declined,—
| Nom. | trēs | tria |
| Gen. | trium | trium |
| Dat. | tribus | tribus |
| Acc. | trēs (trīs) | tria |
| Abl. | tribus | tribus |
4. The hundreds (except centum) are declined like the Plural of bonus.
5. Mīlle is regularly an adjective in the Singular, and indeclinable. In the Plural it is a substantive (followed by the Genitive of the objects enumerated; [§ 201], 1), and is declined,—
| Nom. | mīlia | Acc. | mīlia |
| Gen. | mīlium | Voc. | mīlia |
| Dat. | mīlibus | Abl. | mīlibus |
Thus mīlle hominēs, a thousand men; but duo mīlia hominum, two thousand men, literally two thousands of men.
a. Occasionally the Singular admits the Genitive construction; as, mīlle hominum.
6. Other Cardinals are indeclinable. Ordinals and Distributives are declined like Adjectives of the First and Second Declensions.