The clause ἕως ἂν ζῇ τὸ βουλευτήριον employs a future indicative verb (here contracted as ζῇ) with ἂν to express a temporal limit that is contingent upon a future event. While ἕως with the subjunctive is standard for indefinite or future time, the combination with the future indicative (or periphrastic future) here emphasizes the certainty of the duration's limit rather than mere contingency. Furthermore, the personification of the βουλευτήριον (the Council House) as a living entity capable of 'living' (ζῇ) is a striking rhetorical device; it implies that the political body's institutional existence is the necessary condition for the safety of the citizens, a concept central to the play's satire on the fragility of democracy under the influence of demagogues like Cleon.