Original Text:
LE RÉGISSEUR. - Voyons, mademoiselle faites sonner les RRR... vibrrrez,.... vibrrrez,.... les bonnes traditions se perdent.... de mon temps, au conservatoire, on était parvenu à nous faire vibrer, même en prononçant le mot navet!...

Translation:
THE DIRECTOR: Come on, young lady, the R has got rrrrollll like in purrrrr, purrrrr... at my time at the conservatory we even had to purr the word tulip.
(note : "navet" actually means turnip... which wouldn't make sense in the English translation)