Diphthongs in Phonetics

Diphthong /ǝu/

• Glide: begins between mid-open and mid-close positions, moving towards /u/ above mid-close position
• Jaw: slight closing movement of lower jaw
• Lips: neutral for 1st element, 2nd element lips tend to round
• Starting point: tongue position similar to /3:/

Diphthong /au/

• Glide: begins between back and front open position, moving towards vowel /u/ above close-mid position
• Lips: change from neutrally open to a weakly rounded position
• Jaw: closing movement
• Long: loud, Reduced: shout
• Pulmonic, voiced, oral, wide, falling, closing

Diphthong /eǝ/

• Glide: begins in open-mid front position, moving towards more open variety of /a/ when in final position
• In non-final position, it tends to glide to a mid /ə/ type
• Lips: neutrally open
• Pulmonic, voiced, oral, narrow, falling, centering

Diphthong /1Ə/

• Glide: begins with tongue position of close mid and centralized from front, moving towards more open variety of /ə/
• In non-final position, the glide is not so extensive
• Lips: neutral, with slight movement from slightly spread to neutral
• In unaccented syllables, it is not always falling
• Pulmonic, voiced, oral, falling or rising, centering, narrow

Diphthong /нǝ/

• Glide: begins with tongue position of close mid and centralized from back, moving towards more open variety of /ə/
• In non-final position, the glide is not so extensive
• Lips: weakly rounded at the beginning of the glide and neutrally open as it progresses
• In unaccented syllables, this diphthong may be rising
• Pulmonic, voiced, oral, narrow, centering, falling or rising

Diphthong /eı/

• Glide: begins from slightly below close-mid front position, moving towards /ı/
• Jaw: slightly closing movement
• Quality: starting point is somewhat closer than vowel /e/
• Lips: goes from neutral to slightly spread position
• No change of phoneme in final position
• Pulmonic, voiced, oral, narrow, closing, falling

Diphthong /aı/

• Glide: begins slightly behind front open position, moving towards vowel /ı/
• Requires extensive movement of the tongue
• Lower jaw: closing movement
• Lips: change from neutral to loosely spread position
• Before dark /l/, the /ı/ element is often absorbed into the /ə/ or /u/ glide
• No change of phoneme in final position
• Pulmonic, voiced, oral, falling, closing, wide

Diphthong /oı/

• Glide: begins between open-mid and open-back positions, moving towards vowel /ı/
• Tongue movement: extends from back to centralized front
• Does not require extensive movement of the tongue
• Pulmonic, voiced, oral, falling, closing