Dear MMDs, please let me apologize for my poor English at first, but
I am writing from Germany.  And please do not esteem me meddlesome.
I am German, so I would like to confirm that "Yale" is no German word.
I don't remember ever having heard it.  And the German translation of
"refrain" is "Kehrvers", from "wiederkehren" (to recur) and "Vers"
(the verse).

Best wishes from Germany,
Eberhard Vogel