νέῳ δὲ σιγᾶν μᾶλλον ἢ λαλεῖν πρέπει → it's fitting for a young man to keep silence rather than to speak (Menander)
besides: P. and V. πρὸς τούτοις, ἐπὶ τούτοις, ἔτι, V. καὶ πρός, πρός (rare P.), Ar. and P. προσέτι.
to add a fresh statement: P. καὶ δὴ καί.