Фонетика

The system of vowels Vowels unlike consonants are produced with no obstruction to the stream of air, so on the perception level their integral characteristic is tone not noise. The most important characteristic of these vowels is that they are acous­tically stable.

They are known to be entirely different from one another both articulatory and acoustically.

Consequently they may well be said to form boundaries of the"phonetic field of vowels"

in modern man's language. The quality of a vowel is known to be detennined by the size, volume and the shape of the mouth resonator which are modified by the movement of ac­tive speech organs, i. e. the tongue and the lips. Besides, the particular quality of a vowel can depend on a lot of other factors (articulatory characteristics) such as the relative stability of the tongue, the position of the lips, physical duration of the segment, the force of articulation, the degree of tenseness of speech organs. So vowel quality could be thOUght of as a bundle of definite articulatory characteristics which are sometimes interconnected and interde­pendent: the back position of the tongue makes it rise higher in the mouth cavity, the lengthening of a vowel makes the organs of speech tenser at the moment of production and so on. So the isolation and distinction of the above-mentioned articulatory features are made for the sake of analysis with the purpose of describing the vocalic system of the English language. The analysis of the articulatory constituents of the quality of vowels al­lowed phoneticians to suggest the criteria for classificatory description. They are:

a) stability of articulation

b) tongue position

c) lip position

d) character of the vowel end

e) length

f) tenseness

In the part that follows each of the above-mentioned factors will be considered from phonological point

Of view. Stability of articulation specifies the actual position of the articulating organ in the process of

the articulation of a vowel. There are two possible varieties:

a) the tongue position is stable;

b) it changes, that is the tongue moves from one position to another.

In the first case the articulated vowel is relatively pure, in the second case the vowel consists of two clearly perceptible elements. There exists a third variety; an intennediate case, when the change in the tongue position is fairly weak. So according to the principle of stability of articulation the English vowels are divided into:

• Monophthongs

• Diphthongs

• Diphthongoids

The position of the tongue, another principle for consideration, is char­acterized from two aspects:

horizontal and vertical movement. According to the vertical movement three classes of vowels are distin­guished, each of which is realized in one of the two variants, broad or narrow: close, mid , narrow. According to the horizontal movement five classes of vowels are distin­guished:

1) front: [i:], [e], [~], [£(a)];

2) front retracted: [I), [I(a)];

3) central: [3:], [a], [3(U)], [a(u)J, [a(I)]; .

4)back: [n], [;:,:J, [u:J, [a:], [;:,(r)];

5) back adVanced: [u], [u(a)].

Lip rounding is another articulatory feature which is included into the principles of classification

of English vowels. Traditionally three lip posi­tions are distinguished: spread, neutral and rounded.

For the purpose of classification it is sufficient to distinguish between two lip positions: round­ed and

unrounded or neutral.