αὐτός, αὐτή, αὐτό
 1. myself, yourself, himself.... |
| 2. the same |
As far as accentuation is concerned, no problem, the stress/pitch stays on the last syllable.
Acute changes to circumflex in genitive and dative (singular and plural). Exactly like in nouns.
| singular | plural | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| masculine | neuter | feminine | masculine | neuter | feminine | |||||||||||||||||
| nom | αὐτ | ός | αὐτ | ό | αὐτ | ή | nom | αὐτ | οί | αὐτ | ά | αὐτ | αί | |||||||||
| gen | αὐτ | οῦ | αὐτ | ῆς | gen | αὐτ | ῶν | |||||||||||||||
| dat | αὐτ | ῷ | αὐτ | ῇ | dat | αὐτ | οῖς | αὐτ | αῖς | |||||||||||||
| acc | αὐτ | όν | αὐτ | ό | αὐτ | ήν | acc | αὐτ | ούς | αὐτ | ά | αὐτ | άς | |||||||||