κοινὴ γὰρ ἡ τύχη καὶ τὸ μέλλον ἀόρατον → fortune is common to all, the future is unknown | fortune is common to all and the future unknown | fate is common to all and the future unknown
κενοπονῶ, -έω (Α)
κοπιάζω μάταια, ματαιοπονώ.
[ΕΤΥΜΟΛ. < κεν(ο)- + -πονῶ (< -πόνος < πόνος), πρβλ. ματαιο-πονώ, φιλο-πονώ].