Graeca sunt, non leguntur

[Ed Cryer]

Medieval scribes working on Latin texts would sometimes come across
Greek words; very popular in books by Cicero et al. In the margin they'd
write "Graeca sunt, non leguntur". It's in Greek, and we don't read that.

Look here;
http://www.sarantakos.com/language/graecumest.htm

Ελληνικά είναι, δεν διαβάζονται
I'm sure I don't need translate that here; nor ponder too long on the
main theme of the article itself. Especially so as I've been to Greece
and seen just how young people display a shame with their native language.

Ed