| sg | pl | |||||||
| Masculin | Feminin | Neutru | Masculin | Feminin» | Neutru | |||
| N | ἀγαθός | ἀγαθή | ἀγαθόν | ἀγαθοί | ἀγαθαί | ἀγαθά | ||
| G | ἀγαθοῦ | ἀγαθῆς | ἀγαθοῦ | ἀγαθῶν | ἀγαθῶν | ἀγαθῶν | ||
| D | ἀγαθῷ | ἀγαθῇ | ἀγαθῷ | ἀγαθοῖς | ἀγαθαῖς | ἀγαθοῖς | ||
| A | ἀγαθόν | ἀγαθήν | ἀγαθόν | ἀγαθούς | ἀγαθάς | ἀγαθά | ||
| V | ἀγαθέ | ἀγαθή | ἀγαθόν | ἀγαθοί | ἀγαθαί | ἀγαθά |