All vowel and consonant ω-verbs inflect the first aorist alike.666
Indicative.—The secondary endings of the first aorist active were originally added to the stem ending in -ς-; thus, ἐλυ_ς, ἐλυ_ς-ς, ἐλυ_ς-τ, ἐλυ_ς-μεν, ἐλυ_ς-τε, ἐλυ_ς-ντ. From ἐλυ_ς came ἔλυ_σα (by 35 c), the α of which spread to the other forms except in the 3 sing., where ε was borrowed from the perfect.
a. In the middle the secondary endings are added to the stem ending in -σα-. For the loss of ς in -σο, see cross465 b.667
Subjunctive.—In the subjunctive the long thematic vowel -ώη- is substituted for the α of the indicative, and these forms are inflected like the present subjunctive: λύ_σω λύ_σωμαι, φήνω φήνωμαι. For the loss of ς in -σαι see cross465 a.667D
Hom. has forms with the short thematic vowel, as ἐρύσσομεν, ἀλγήσετε, νεμεσήσετε; μυ_θήσομαι, ἐφάψεαι, ἱ_λασόμεσθα, δηλήσεται. In such forms aorist subjunctive and future indicative are alike ( cross532). Pindar has βά_σομεν, αὐδά_σομεν ( cross457 D.).668
Optative.—To the stem ending in α the mood-suffix ι_ is added, making αι, to which the same endings are affixed as in the present: λύ_σα-ι_-μι λύ_σαιμι, λυ_σα-ί_-μην λυ_σαίμην, φήνα-ι_-μι φήναιμι. The inflection in the middle is like that of the present. For the loss of ς in -σο see cross465 b.—In the active -ειας, -ειε, -ειαν are more common than -αις, -αι, -αιεν.668D
Hom. has both sets of endings, but that in αι is rarer. In the drama -ειας is very much commoner than -αις. -αις is most frequent in Plato and Xenophon, less common in poetry, and very rare in the orators. Neither Thuc. nor Hdt. has -αις. -αι is rare in prose, most examples being in Plato and Demosthenes. Hdt. has no case. In Aristotle -αι is as common as -ειε. -αῖεν is very rare in poetry, in Thuc. and Hdt., but slightly better represented in Xenophon and the orators. -ειαν is probably the regular form in the drama.—The forms in -ειας, -ειε, -ειαν are called “Aeolic,” but do not occur in the remains of that dialect.
Imperative.—The regular endings ( cross462) are added to the stem in -σα (or -α in liquid verbs) except in the active and middle 2 sing., in which -ον and -αι take the place of -α: λῦσον λυ_σάτω, λῦσαι λυ_σάσθω, φῆνον φηνάτω, φῆναι φηνάσθω.670
Infinitive.—The aorist active infinitive ends in -αι, which is an old dative: the middle ends in -σθαι: λῦσαι λύ_σα-σθαι, φῆναι φήνα-σθαι, πλέξαι πλέξα-σθαι.671
Participle.—The active participle adds -ντ like the present: masc. λύ_σα_ς from λυ_σαντ-ς, fem. λύσα_σα from λυσα_ντ-yα, neut. λῦσαν from λυ_σαν (τ). See cross301. The middle ends in -μενος: λυ_σά-μενος, φηνά-μενος.671D
Aeolic has -αις, -αισα, -αν ( cross37 D. 3).
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].