Movable N may be added at the end of a word when the next word begins with a vowel. Movable ν may be annexed to words ending in -σι; to the third person singular in -ε; and to ἐστί
Thus, πᾶσιν ἔλεγεν ἐκεῖνα
a. Except ἐστί, words that add ν do not elide their final vowel ( cross73).
b. Verbs in -εω never (in Attic) add -ν to the 3 sing. of the contracted form: εὖ ἐποίει αὐτόν
N.—Movable ν is called ν ἐφελκυστικόν (
Herbert Weir Smyth [n.d.], A Greek Grammar for Colleges; Machine readable text [info] [word count] [Smyth].