νέῳ δὲ σιγᾶν μᾶλλον ἢ λαλεῖν πρέπει → it's fitting for a young man to keep silence rather than to speak (Menander)
P. φιλοπόνως.
zealously: P. and V. σπουδῇ, προθύμως, P. σπουδαίως.
preservingly: V. ἐμπέδως.