Σκηνὴ πᾶς ὁ βίος καὶ παίγνιον: ἢ μάθε παίζειν, τὴν σπουδὴν μεταθείς, ἢ φέρε τὰς ὀδύνας → All life is a stage and a play: either learn to play laying your gravity aside, or bear with life's pains.
a sound: V. ἀντιφθέγγεσθαι, ἀνταλαλάζειν; see echo.
reecho (a sentiment): use P. and V. ἐπαινέω, ἐπαινεῖν; see approve.