Phonetics - Unit Three - Lesson No. 14
Vowels are made by voiced air passing through different mouth shapes. The differences in the shape of the mouth are caused by different positions of the tongue and lips. It is easy to see and to feel the lip difference, but it is very difficult to see or feel the tongue differences, and that is why a detailed description of the tongue positions for a certain vowel does not really help us to pronouns it well.
Vowels must be learned by listening and imitating. For example, the English vowel /o:/ as in “saw” is made by rounding the lips and by placing the back of the tongue in a position mid-way between the highest possible and the lowest possible position, but it could be much more helpful if the sound is pronounced for a speaker to learn or imitate. English vowels exhibit a great deal of variation from dialect to dialect, e.g. there is a great variation in the vowels of Australian English and American English as well as the British English. However, the standard pronunciation in Britain is the Received Pronunciation, or what is referred to as the BBC pronunciation. That is the same way of pronunciation which is followed by the British Broadcast Corporation.