12.Classification of English vowels according to the stability of articulation. Diphthongs. Mistakes typical of Russian learners of English and ways of correcting them.
Vowels are normally made with the air stream that meets no closure
or narrowing in the mouth, pharyngal and nasal cavities. That is why in the production of vowel sounds there is no noise component characteristic of consonantal sounds.
According to the stability of articulation there are 3 groups of vowels:
monophthongs, diphthongs and diphthongoids.
Monophthongs are vowels the articulation of which is almost unchanging. The quality of such vowels is relatively pure. Most Russian vowels are monophthongs. The English monophthongs are: [i, e, ae, a, o, o:, u
, a].
In the pronunciation of diphthongs the organs of speech glide from one vowel position to another within one syllable.
The starting point,
the nucleus, is strong and distinct. The glide which shows the direction of the quality change is very weak. In fact diphthongs consist of two clearly perceptible vowel elements. There are no diphthongs in Russian. The English diphthongs are: [ei, ai, oi, au,, ie]
.
In the pronunciation of diphthongoids the articulation is slightly changing but the difference between the starting point and the end is not so distinct as it is in the case of diphthongs. There are two diphthongoids in English: [i:, u:]. The initial "o" may serve as an example
of a Russian diphthongoid, eg
очень
.
