| Nominativ | improbus, improba, improbum, imbrobus, improbabiles, improbabilibus, improbabilis, improbalitas | improbi, improba, improbiusque, imbrobi, improbabiles, improbabilibus, improbabilis, improbae, improbalitas, improbiorem, improbiter |
| Genitiv | improbi, improbiusque, imbrobi, improbae, improbiorem, improbiter | improborum, improbarum |
| Dativ | improbo, improbae | improbis, improbissimi, improbissimum, improbissima, improbissimis, improbissimae, improbissimo, improbissimorum, improbissimus, improbissimam, improbissime, improbissimos, improbissimas |
| Akkusativ | improbum, improbam | improbos, improbas, improba, imbrobos, improbabiles, improbabilibus, improbabilis, improbalitas, improbossime, improbossus |
| Ablativ | improbo, improba, improbabiles, improbabilibus, improbabilis, improbalitas | improbis, improbissimi, improbissimum, improbissima, improbissimis, improbissimae, improbissimo, improbissimorum, improbissimus, improbissimam, improbissime, improbissimos, improbissimas |
| Vokativ | improbum, improba, improbe, improbabiles, improbabilibus, improbabilis, improbalitas | improbi, improba, improbiusque, imbrobi, improbabiles, improbabilibus, improbabilis, improbae, improbalitas, improbiorem, improbiter |