Classifying the Vowels Sounds of English
The classifcation of vowels is based on four major aspects:
Tongue height - according to the vertical position of the tongue (high vowels, also referred to as close; low vowels, also referred to as open; intermediate - close-mid and open-mid) Frontness vs. backness of the tongue - according to the horizontal position of the highest part of the tongue. Lip rounding - whether the lips are rounded (O-shape) or spread (no rounding) when the sound is being made. Tenseness of the articulators - refers to the amount of muscular tension around the mouth when creating vowel sounds. Tense and lax are used to describe muscular tension. | Front vowels(tongue body is pushed forward) | Central vowels(tongue body is neutral) | Back vowels(tongue body is pulled back) | High/close vowels(tongue body is raised) | /http://www.studyenglishtoday.net/Phon_symb/pi.gif/ see/http://www.studyenglishtoday.net/Phon_symb/iletter.gif/ sit | | /http://www.studyenglishtoday.net/Phon_symb/pu.gif/ boot/http://www.studyenglishtoday.net/Phon_symb/upsilon.gif/ book | Mid vowels(tongue body is intermediate) | /e/ bait*/http://www.studyenglishtoday.net/Phon_symb/epsilon.gif/ bet | /http://www.studyenglishtoday.net/Phon_symb/schwa.gif/ sofa**, /http://www.studyenglishtoday.net/Phon_symb/pe.gif/ bird | /o/ boat*/http://www.studyenglishtoday.net/Phon_symb/po.gif/ bought*** | Low/open vowels(tongue body is lowered) | /http://www.studyenglishtoday.net/Phon_symb/pshorta.gif/ bat | /http://www.studyenglishtoday.net/Phon_symb/caret.gif/ under** | /http://www.studyenglishtoday.net/Phon_symb/pa.gif/ father, /http://www.studyenglishtoday.net/Phon_symb/pho.gif/ sock(BrE) |
*In some American accents (especially Californian English), vowel sounds in words such as bait, gate, pane and boat, coat, note are not consider diphthongs....