The obituaries for the great comic Sid Caesar invariably mention his proficiency in "double-talk," mimicking the sounds (but not the sense) of foreign languages. It turns out that this was a talent Caesar had cultivated ever since he was a boy clearing tables at his father's restaurant in multi-ethnic Yonkers.
The New York Times:
He could seem eloquent even when his words were total gibberish: Among his gifts was the ability to mimic the sounds and cadences of foreign languages he didn’t actually speak.
Some of Caesar's most popular bits were built around pompous or outlandish characters—such as Professor von Votsisnehm—in which he spoke in a thick accent or mimicked foreign languages in comic but convincing gibberish.
"He was the ultimate, he was the very best sketch artist and comedian that ever existed," [Carl] Reiner said of his friend. "His ability to double talk every language known to man was impeccable."
One of his virtuosic double-talk performances is captured on YouTube—in the space of five minutes he moves from fake French to fake German to fake Italian to fake Japanese:
So how did Caesar get to be so good at double-talk? He goes into great detail in his memoir, Caesar's Hours: My Life in Comedy, with Love and Laughter:
While I greatly admired Caesar's chops in double-talk, I always felt he was at his funniest when he said hardly anything at all.
A version of this post appeared on Language Log.