Accent and Accent-Marking in Ancient Greek
The Last 3 Syllables and the Accents
The antepenult may be accented only if U is short and may receive only the acute. This restriction is again explained by the general rule of contonation and mora.
ἄνθρωπος – U must be short
ἄνθρωποι – U must be short
ὤφελον – U must be short