Herbert Weir Smyth, A Greek Grammar for Colleges

a. Both εἴτε clauses may have the same finite verb in common, which verb is used only once; as ““εἴτε βούλεσθε πολεμεῖν ἡμῖν εἴτε φίλοι εἶναι” whether you wish to wage war upon us or to be our friends” X. C. 3.2.13.

b. Each εἴτε clause has its own verb and its own main clause; as ἐκέλευσέ σε, εἴτε πάντας αἰτιᾷ, κρί_ναντα σὲ αὐτὸν χρῆσθαι ὅ τι ἂν βούλῃ, εἴτε ἕνα τινὰ ἢ δύο . . . αἰτιᾷ, τούτους ἀξιοῦσι παρασχεῖν σοι ἑαυτοὺς εἰς κρίσιν the army requests that, if you accuse all, you pass sentence on them and treat them as you may think best; or, if you accuse one or two, they think it right that these men should surrender themselves to you for judgment X. A. 6.6.20.

c. One main clause refers to both εἴτε clauses; as ““ὁ ἀγαθὸς ἀνὴρ . . . εὐδαίμων ἐστὶ . . . ἐά_ν τε μέγας καὶ ἰσχυ_ρός, ἐά_ν τε σμι_κρὸς καὶ ἀσθενὴς ᾖ” the good man is happy whether he is large and strong or small and weak” P. L. 660e.

d. Neither εἴτε clause has a verb, which is to be supplied from the main clause; as λέγοντες, εἴτ᾽ ἀληθὲς εἴτ᾽ ἄρ᾽ οὖν μάτην (ἔλεγον) saying, whether truly or after all, it may be, falsely S. Ph. 345.

e. One εἴτε clause has its own verb, while the other gets its verb from the main clause (rare); as ἐμοὶ σὺ . . . φαίνῃ . . . χρησμῳδεῖν, εἴτε παρ᾽ Εὐθύφρονος ἐπίπνους γενόμενος (χρησμῳδεῖς), ““εἴτε καὶ ἄλλη τις μοῦσα πάλαι σε ἐνοῦσα ἐλελήθει” you seem to me to utter prophecies, whether you were inspired by Euthyphron or whether some other muse has long been present in you without your knowing it” P. Crat. 428c.