Editing Vowel shift (section)

===Canadian Raising===
There is another characteristic found in Canadian English called Canadian Raising. This feature includes the vowel diphthongs onsets of /aj/ and /aw/ raise to mid vowels when they precede voiceless obstruents (the sounds /p/, /t/, /k/, /s/, and /f/).  Canadian pronunciation of "about" often sounds like "aboot", pronunciation of /aw/ is articulated with the tongue in a low position, and because it raises to a mid position in Canadian English when the vowel precedes the voiceless obstruents listed above. Speakers of other varieties of English will immediately detect the vowel raising, but will sometimes think that the vowel has raised farther than it actually does, all the way to /u/. The raised vowels /aɪ/ typically raises [ɐɪ], while the raised variant of /aʊ/ differs by dialects in Canada, with [ɐʊ~ʌʊ] more common in Western Canada and a fronted variant [əʊ~ɛʊ] is mostly heard in Central Canada.<ref>Boberg, Charles (2004). "English in Canada: phonology". In Schneider, Edgar W.; Burridge, Kate; Kortmann, Bernd; Mesthrie, Rajend; Upton, Clive (eds.). A Handbook of Varieties of English. Volume 1: Phonology. Mouton de Gruyter. pp. 351–365. {{ISBN|978-3-11-017532-5}}.</ref> The open vowel component of the diphthongs changes to a mid vowel ([ʌ], [ɐ], [ɛ] or [ə]).