Accent and stress rules for present verbs ending in -ω and related endings (-βω, -πω); conditions causing oxytonicity or barytonicity; examples and conditioning by preceding syllables or vowel length.
Βατράχοις ( 37) «παῖ, ἠμί, παῖ», ἐξ οὗ τὸ ἦ τὸ σημαῖνον τὸ εἶπον οἷον «ἦ καὶ κυανέῃσιν ἐπ´ ὀφρύσι νεῦσε Κρονίων» (Α 528) καὶ «ἦ ῥα καὶ ἐξ ὀχέων» (Δ 419)—ὀξύνεται. ταῦτά ἐστι τῶν ῥημάτων τὰ ὀξυνόμενα. εἰ δέ τί ἐστιν ἄλλο ἐπὶ τέλους ἔχον τὸν τόνον, περισπᾶται ποιῶ νοῶ, ποιοῦ νοοῦ, ποιεῖν νοεῖν καὶ τὰ τοιαῦτα. Πᾶν ῥῆμα εἰς 'ω' μονοσύλλαβον περισπᾶται, ζῶ, κλῶ, κνῶ, θλῶ, δρῶ, ἐὰν βῶ, ἐὰν στῶ. λείπεται τοίνυν διασαφηνίσαι τὴν τῶν εἰς 'ω' ληγόντων ἐνεστώτων τάσιν κατὰ τὰς ἑαυτῶν συζυγίας. Τὰ εἰς 'βω' λήγοντα βαρύνεται. τότε περισπᾶται, ὅτε ἐν ταῖς δυσὶ συλλαβαῖς ἔχει τὸ 'β', ἢ ὄνομα προϋπάρχει ἢ τὸ 'ο' ἔχει ἐν τῇ παραληγούσῃ ἢ τὸ 'ω' μέγα. καὶ βαρύνεται μὲν ταῦτα, λείβω καὶ κατὰ ἀποβολὴν τοῦ 'λ' εἴβω, τρίβω, στείβω, φέρβω, ἀμείβω, σέβω, φέβω τὸ φοβοῦμαι, ῥέμβομαι, θλίβω, στίλβω. περισπᾶται δὲ ταῦτα ὡς ἔχοντα ἐν δυσὶ συλλαβαῖς 'β' βαυβῶ τὸ καθεύδω, βομβῶ, βιβῶ τὸ περιπατῶ. ἔτι περισπῶνται τὰ ἔχοντα προϋπάρχοντα ὀνόματα, φόβος φοβῶ, ἀσεβής ἀσεβῶ, εὐσεβής εὐσεβῶ, θόρυβος θορυβῶ, κόλυμβος κολυμβῶ, λαβή λαβῶ. τὸ γὰρ λάβω ὑποτακτικόν ἐστι τοῦ ἔλαβον. Ἔτι περισπῶνται τὰ ἔχοντα 'ο' μικρὸν ἢ 'ω' μέγα ἐν τῇ παραληγούσῃ, σοβῶ, στροβῶ, κολοβῶ, λωβῶ. Τὰ εἰς 'πω' λήγοντα βαρύνονται, εἰ μὴ παραλήγοιτο τῷ 'υ' ἢ τῷ 'ω', ἢ εἰ μὴ παρώνυμα εἴη ἢ ἐν τῇ πρώτῃ καὶ δευτέρᾳ συλλαβῇ ἔχοι τὸ 'π' θάλπω, λάμπω, πέμπω, λείπω, μέλπω, βλέπω, ἐρείπω τὸ καταβάλλω, ἕρπω, δρέπω, ἕπω, τρέπω, σκέπω, λέπω, ἔπω τὸ ἐνέπω. πρόσκειται «εἰ μὴ ἔχοι ἐν τῇ πρὸ τέλους τὸ 'υ' ἢ τὸ 'ω'» διὰ τὸ γνυπῶ τὸ γονυπετῶ καὶ κλωπῶ τὸ κλέπτω, ὅθεν καὶ κλώψ. τὸ δὲ «εἰ μὴ παρώνυμα εἴη» διὰ τὸ κόπος κοπῶ, ἶπος ἡ παγίς ἰπῶ τὸ βλάπτω,
In the Frogs (37): “παῖ, ἠμί, παῖ”, from which comes ἦ, meaning “I said”, as in “ἦ καὶ κυανέῃσιν ἐπ᾽ ὀφρύσι νεῦσε Κρονίων” (Α 528) and “ἦ ῥα καὶ ἐξ ὀχέων” (Δ 419)—it is accented with an acute. These are the verbs that are accented with an acute. But if there is anything else that has the accent on the final syllable, it is circumflexed: ποιῶ, νοῶ, ποιοῦ, νοοῦ, ποιεῖν, νοεῖν, and the like. Every monosyllabic verb in -ω is circumflexed: ζῶ, κλῶ, κνῶ, θλῶ, δρῶ, ἐὰν βῶ, ἐὰν στῶ. It remains, then, to make clear the accentuation of the present tenses ending in -ω according to their respective conjugations.
Those ending in -βω are accented with a grave. They are circumflexed when, in the two syllables, they have β, or when a noun pre-exists, or when they have ο in the penult, or a long ω. And these are accented with a grave: λείβω, and by loss of λ, εἴβω; τρίβω, στείβω, φέρβω, ἀμείβω, σέβω, φέβω meaning φοβοῦμαι, ῥέμβομαι, θλίβω, στίλβω. But these are circumflexed, as having β in two syllables: βαυβῶ meaning καθεύδω, βομβῶ, βιβῶ meaning περιπατῶ. Further, those are circumflexed that have pre-existing nouns: φόβος, φοβῶ; ἀσεβής, ἀσεβῶ; εὐσεβής, εὐσεβῶ; θόρυβος, θορυβῶ; κόλυμβος, κολυμβῶ; λαβή, λαβῶ. For λάβω is the subjunctive of ἔλαβον. Further, those are circumflexed that have short ο or long ω in the penult: σοβῶ, στροβῶ, κολοβῶ, λωβῶ.
Those ending in -πω are accented with a grave, unless the penult has υ or ω, or unless they are denominatives, or unless in the first and second syllable they have π: θάλπω, λάμπω, πέμπω, λείπω, μέλπω, βλέπω, ἐρείπω meaning καταβάλλω, ἕρπω, δρέπω, ἕπω, τρέπω, σκέπω, λέπω, ἔπω meaning ἐνέπω. The addition “unless it has in the syllable before the end υ or ω” is because of γνυπῶ meaning γονυπετῶ and κλωπῶ meaning κλέπτω, whence also κλώψ. And the clause “unless it is denominative” is because of κόπος, κοπῶ; ῖπος, the snare, ἰπῶ meaning βλάπτω.