English vowel sounds

Vowels are open sounds because they involve no obstruction to the flow of air from the lungs as it passes up through the windpipe (trachea), through the voice box (larynx) and out of the mouth. Other than positioning the tongue, jaws and lips there is nothing to obstruct the airflow. All vowels are produced with the vocal folds vibrating and are said to be voiced sounds.

Vowels are commonly described according to the following characteristics:

The portion of the tongue that is involved in the articulation: front, central or back.
The tongue's position relative to the palate: high, mid or low.
The shape of the lips: rounded or unrounded (spread).
The length or duration of vocalization: long or short.

A four-sided vowel chart is often used to demonstrate the front–back and high–low positions. The chart roughly represents the tongue position in the oral cavity.

The vowels used in Pronunciation Coach for American English are described in the following table. Click on the video links to watch a short 3D animation of how each vowel is produced.

Phonetic symbol	Example	Tongue	Lips	Length
/i/	cream	high-front	unrounded	long
/ɪ/	bit	high-front	unrounded	short
/e/	lake	mid-front	unrounded	long
/ɛ/	bet	mid-front	unrounded	short
/æ/	cat	low-front	unrounded	short
/ɚ/	burn	high-central	rounded	long
/ʌ/	cut	mid-central	unrounded	short
/ə/	about	mid-central	unrounded	short
/u/	boot	high-back	rounded	long
/ʊ/	put	high-back	rounded	short
/o/	over	mid-back	rounded	long
/ɔ/	corn	mid-back	rounded	long
/ɑ/	hard	low-back	unrounded	long

Pronunciation Coach 3D

Pronunciation Coach 3D uses state-of-the-art computer animation and 3D modelling techniques to illustrate how to pronounce all of the sounds in the English language, and how to combine these sounds to pronounce any word or sentence.

Diphthongs

A diphthong is a long, complex vowel which starts with the sound quality of one vowel and ends with the sound quality of another one. Although they are classified as single phonemes, diphthongs are given a double symbol to show both the quality they start with and the quality they end with.

Phonetic symbol	Example	Tongue	Lips	Length
/ɑɪ/	bite	moves from a low back position to a mid-high front position	unrounded	long
/ɑʊ/	brown	moves from a low back position to a mid-high back position	move from unrounded to rounded	long
/ɔɪ/	boy	moves from a low-mid back position to a mid-high front position	move from rounded to unrounded	long

Vowel Sounds