them mainly through increased lip rounding of the former, but many speakers use only the latter phoneme, especially most speakers in northern France such as Paris (but not farther north, in Belgium). In some dialects, particularly that of Europe, there is an attested tendency for nasal vowels to shift in a counterclockwise direction: tends to be more open and shifts toward the vowel space of (realised also as ), rises and rounds to (realised also as ) and shifts to or . Also, there also is an opposite movement for for which it becomes more open and unrounds to , resulting in a merger of Standard French and in this case. According to one source, the typical phonetic realization of the nasal vowels in Paris is for , for and for , suggesting that the first two are unrounded open vowels that contrast by backness (like the oral and in some accents), whereas is much closer than . In Quebec French, two of the vowels shift in a different direction: → , more or less as in Europe, but → and → . In the Provence and Occitanie regions, nasal vowels are often realized as oral vowels before a stop consonant, thus reviving the otherwise lost in other accents: quarante → . Contrary to the oral , there is no attested tendency for the nasal to become central in any accent. Schwa When phonetically realised, schwa (), also called e ('dropped e') and e ('mute e'), is a mid-central vowel with some rounding. Many authors consider it to be phonetically identical to . Geoff Lindsey suggests the symbol . state, more specifically, that it merges with before high vowels and glides: → ('clarity'), → ('workshop'), in phrase-final stressed position: dis-le ! → ('say it'), and that it merges with elsewhere. However, some speakers make a clear distinction, and it exhibits special phonological behavior that warrants considering it a distinct phoneme. Furthermore, the merger occurs mainly in the French of France; in Quebec, and are still distinguished. The main characteristic of French schwa is its "instability": the fact that under certain conditions it has no phonetic realization. That is usually the case when it follows a single consonant in a medial syllable: → ('to call'), It is occasionally mute in word-final position: → ('door'). Word-final schwas are optionally pronounced if preceded by two or more consonants and followed by a consonant-initial