The problem of vowel length

SEGMENTAL PHONETICS AND PHONOLOGY: VOWELS

In any language sounds are traditionally divided into vowels and consonants. In the articulatory aspect the main principles of such subdivisions are: the presence or absence of obstruction, the distribution of muscular tension, the force of the air stream coming from the lungs. Vowel sounds are based on voice (tone) which is modified in the pharynx, oral and nasal cavities. There is no obstruction in their articulation. The muscular tension is spread evenly throughout the speech organs. The force of the air stream is rather weak. The articulatory boundary between vowels and consonants is not clearly marked. The sonorants (or approximants) occupy an intermediate position between vocalic and consonantal characteristics. From the acoustic point of view vowels are complex periodic vibrations – tones. They are combinations of the main tone and overtones intensified by the oral and nasal cavities.

In describing the articulatory characteristics of any speech sound it is necessary to consider two main notions – the quality of a sound and the quantity of a sound. The quantity of a sound means its length characteristics, either e.g. a sound is long or short. The quality of a sound means such features as the place of articulation, the active organ of speech etc.

The most widely spread and illustrative descriptions and classifications of speech sound are based on their articulatory characteristics. For the graphic presentation the Vowel space (Vowel Quadrilateral (trapezium) or Vowel Chart) is used.

The articulatory classification of English vowels

The articulatory classification of English vowels is based on several principles. They are: 1) the stability of articulation; 2) the tongue position; 3) the lip position; 4) the energy discharge; 5) the historical length; 6) the tenseness.

The articulation of a vowel may be either stable or not. It is stable when the organs of speech do not change their position during the production of a vowel. There exist three possibilities: 1) the articulation is stable – in such a way monophthongs are pronounced; 2) the position of the speech organs change during the production of a vowel – a vowel is a diphthong and 3) when the positions of the organs of speech change but not so much as for a diphthong, a vowel is a diphthongoid. There are two diphthongoids in the English vowel system - /i:/ and /I/. There are eight diphthongs and ten monophthongs.

The tongue can move in two directions: vertical and horizontal. According to the tongue position all the vowels are divided first judging by the vertical (up/down) movement or the height of the tongue or horizontal (forward/backward) position. When the bulk of the tongue is moved to the front part of the mouth, it is a front vowel. When the tongue lies flat, it is a central vowel. When the bulk of the tongue is moved to the back part of the mouth, it is the case for back vowels. There also exist front-retracted and back-advanced vowels.

According to the height of the tongue the following types of vowels can be singled out: 1) high (close) – when the tongue is high in the mouth; 2) low (open) – when the tongue moves down, usually with the lowering of the lower jaw; 3) the middle positions – mid-high and mid-low – when the tongue is neither high nor low in the mouth. In each of the three groups “narrow” and “broad” subgroups are sometimes singled out.

Lips may be rounded, neutral or spread. For the classification of vowels two parameters exist: rounded and unrounded (neutral + spread positions). Four English vowels are rounded, all the others are unrounded.

All the other three characteristics of vowels are closely connected. The energy discharge suggests two terms: checked and unchecked (free). It is based on the character of the articulatory transition from the vowel to the following consonant. Generally speaking, all the historically long vowels are unchecked (free), all the historically short vowels are checked.

The relevant features of the English vowel phonemes.

The problem of vowel length

The length of English vowels is positionally conditioned. That is why only two characteristics of vowels may be called relevant. They are the stability of articulation and the tongue position.

CONSONANTS

Consonants are speech sounds in the articulation of which there is an obstruction, the removal of which causes noise – plosion or friction. The muscular tension is concentrated at the place of obstruction. The air stream is strong. From the acoustic point of view consonants are non-periodic vibrations – noises. Voiceless consonants are pure noises. Voiced consonants are combinations of noise and tone.

There also exists an intermediate group of sounds – sonorants (or approximants). They are tones with the admixture of noise. The sonorants are close to consonants because in their production there is an obstruction and the muscular tension is concentrated at the place of obstruction. They are close to vowels because they are based on voice and the force of the air stream is rather week. Moreover, in the English language some sonorants in some positions may be syllabic, but it is not regularity. So, first of all, consonants in English are subdivided into noise consonants and sonorants.

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