| Singular | Plural | |
|---|---|---|
| Nominativ | regula, regulaeque, regula | regulae, regulae |
| Genitiv | regulae, regulai, regulae, regulai | regularum, regularum |
| Dativ | regulae, regulai, regulae, regulai | regulis, regulabus, regulis, regulabus |
| Akkusativ | regulam, regulam | regulas, regulas |
| Ablativ | regulad, regulad, regula, regulaeque, regula | regulis, regulabus, regulis, regulabus |
| Vokativ | regula, regulaeque, regula | regulae, regulae |