Roger Mills scripsit:

> Depends on a number of factors-- (1) the area-- whether it's an Eastern
> (Romanian and IIRC Italian and some small relatives) or Western
> (Franco-Provencal/Iberian). (2) whether the VL vowel system goes to 5
> /ieauo/ (maybe with length), or 7 /ieEauoO/ (or more, like French, but it's
> another matter).

French actually descends from the Western Romance 7-vowel system -- it's
just that all seven vowels except /i/ became diphthongs and then were
resolved to monophthongs later.

As for the original Latin diphthongs, ae and oe went to /E:/ and /E/
(or is it the other way around?) long ago; au went to /o/ much later
and quite sporadically (Spanish and French yes, Portuguese no).
A new source of diphthongs was non-stressed i before another vowel.

"May the hair on your toes never fall out!"     John Cowan
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