This language differentiates front-rounded from back-rounded vowels, as in vu, "seen" & vous, "you"
..... 
either because allophones are differentiated, or because the phonetic quality of 
the... [DOC] [TLE] Introduction to Phonetics for Students of English, French, German ... [PAR] material here to serve as the starting-point for subsequent language-specifc 
Phonetics ..... Having seen these diagrams, you should be able to sense the high/
low difference ....