First it is necessary for us to have a closer look at the way

Long mid back rounded monophthong

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Short high back rounded monophthong

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Long high back rounded monophthong

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Long mid central unrounded monophthong

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Short mid central unrounded monophthong

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*Theoretical ground taken from: Forel, A and Puskás, G (2005) 
Phonetics and Phonology: Reader for First Year English 
Linguistics. University of Geneva.
*Presentation designed by: Manuel R. Medina (2016)