Theme : vowels and their classification in modern english

1.2.Vowel-consonant distinctions

I just want to tell that it is important to know distinctions between vowels and consonants. We try to show some distinctions between them in this chapter. We discussed about vowels enough above and now we should define what a consonant is. A consonant is a speech sound made by partially or completely blocking the flow of air through the mouth (using the lips, teeth, tongue, and palate). Letters of the English alphabet that represent consonants include all the letters that are not vowels The letter “y” makes a consonant sound when it appears at the beginning of words (examples: yellow, yacht), and it makes a vowel sound when it appears at the end of words (examples: valley, fairy).The distinction between them is discussed below.
Consonants and vowels are two different qualities of sounds that are found almost in all languages of the world. The distinctions between them are discussed below. Consonants are defined as the sounds articulated by temporary obstruction in the air stream which passes through the mouth. The obstruction made by the articulators may be 'total', 'intermittent', 'partial', or may merely constitute a narrowing sufficient to cause friction. In the articulation of consonants almost all articualtors are involved. Especially the position of the soft palate causes the division of consonants into 'oral consonants' and 'nasal consonants'. when the soft palate is raised, 'oral consonants' are produced; the soft palate is lowered, 'nasal consonants' are produced. In English /m/, /n/, and / /are nasal consonants and rest of all are oral consonants. The function of vocal cords also causes the division of consonants as 'voiceless' and 'voiced'. When vocal cords are kept apart, voiceless consonants as /p, t, k, f, s, / are produced whereas their vibrations produce voiced consonants as /b, d, g, v, z/. But vowels are the sounds that are produced with an approximation without any obstruction in the air passage.
Among all articulators, only tongue is prominent in their production. All vowel sounds are voiced and all of them are 'oral' as during the production of them the soft palate is raised and hence the nasal cavity is completely blocked. The examples of the vowels are /i, e, a, u, y, o, /. Consonants in phonetics are referred to as 'contoids' which often appear as the marginal elements in the 'syllable'. They seldom form nucleus of the syllable except some case. The consonants 'n' and 'l' in the second syllable of the words 'button' and 'apple' form nucleus. But vowels referred to as 'vocoids' in phonetics always form the nucleus of the syllable as in 'bill', 'pill', 'mill', 'heat', etc. Even in their manner of classification, consonants and vowels show apparent distinction.
Consonants are identified or classified in terms of 'voicing', 'place of articulation', and 'manner of articulation', whereas vowels in terms of the 'height of tongue', 'part of tongue', which is raised or lowered, and 'lip rounding'. Classification of consonants Consonants as discussed above are classified in terms of: 1. voicing 2. place of articulation 3. manner of articulation Voicing. On the basis of voicing, consonants are divided into 'voiced consonants' and 'voiceless consonants'. Voiced consonants are those which are articulated with the vibration of the vocal cords. In English voiced consonants are /b, d, g, j, v, , z/. Voiceless consonants are articulated without vibration of vocal cords or it may be said that during the production of voiceless consonants vocal cords are kept apart. Examples: /p, t, k, f, s, h/. Point of articulation. On the basis of the points of articulation, consonants are divided as: Bilabial (or labial): Both lips as the primary articulators articulate with each other. Examples: /p/, /b/, /m/, /w/. Labio-dental: The lower lip articulates with the upper teeth. Examples: /f/, /v/. Interdental: The tip and the rims of the tongue articulate with the upper teeth. Examples: /ð/. Alveolar: The blade, or top and blade of the tongue articulates with the alveolar ridge (the upper teeth ridge).
Examples: /t/, /d/, /s/, /z/, /n/, /l/, /r/. Palato-alveolar: The blade, or the tip and blade of the tongue articulates with the alveolar ridge and there is at the same time a raising of the front of the tongue towards the hard palate. Examples: /c/, /j/, /s/, /z/, /j/. Velar: A glottal obstruction, or a narrowing causing friction and vibration between the vocal cords. However, some consonants in this category may be produced without vibration between the vocal cords. Examples: /k/, /g/, /h/. Manner of articulation. The manner of articulation describes the different types of obstructions made by the articulators. These obstructions may be total, intermittent, partial or may merely constitute a narrowing sufficient to cause friction. According to the manner of articulation consonants are divided into 'plosives', 'affricates', 'fricatives', 'lateral', 'retroflex', and 'nasals'.
Plosives (stops): For this, there occurs a complete closure at some point in the vocal tract, behind which the air pressure builds up and is released explosively. Examples: /p/, /t/, /k/, /b/, /d/, /g/. Affricates: For this, a complete closure appears at some point in the mouth, behind which the air pressure builds up; the separation of the articulators is slow with that of a plosive, so that friction is a characteristic second element of the sound. Examples: /j/. Fricatives: Two articulators approximate to such an extend that the air stream passes through them with friction. The sounds produced in this way are called fricatives. Fricatives may be voiced as /v/, /f /, /s/, /z/ and voiceless as /f/, /v/, /s/, /s/, /h/. Fricatives differ also in the shape of the narrow opening in which they are produced. In /f/, /v/, /s/, /z / it is relatively wide from side to side but very narrow from top to bottom. Because of this slit like shape of the opening, these sounds are called 'slit fricatives'. In contrast, in /s/, /z/, /c/, /j/, the opening is much narrower from side to side and deeper from top to bottom. These sounds are called 'groove fricative'. Lateral: For lateral, a partial closure is made at some point in the mouth, the air stream being allowed to escape from one or both sides of the contact.
For example, /l/ in 'loud' or 'late'. Retroflex: In the production of this sound, the tip of the tongue is raised towards the alveolar ridge without touching it. The sides of the tongue are pressed against the upper back teeth. As the sound is produced, air flows out over the tip of the tongue and vocal cords vibrate. Example: /r/. Nasals: These sounds are produced with a complete closure at some point in the mouth but the soft palate is lowered and hence the oral cavity is blocked and air escapes through nasal cavity. These sounds are continuants. In the voiced form, they have no noise component. They are, to this extent, vowel like. Examples: /m/, /n/ .

1.3. Problems of classification of vowels

While writing my research work I came across different approaches to the classification of vowels and we will look though some of them and try to compare. Of all the movable organs within the mouth cavity, the tongue is by far the most flexible and is capable of assuming a great variety of positions. Therefore it is the most active resonance-modifier, being responsible for the greatest number of modifications of the shape of the mouth resonator, which ultimately determine different vowel tam- bers. It is for this reason that the main two principles of all current articulatory classifications of vowels are based on the movements and positions of the tongue.
For such classificatory and descriptive purposes, the surface of the tongue is conventionally divided into several parts, although the tongue itself, a complex muscular structure, does not show obvious sections. A convenient basis for such a division is provided by the fixed organs lying opposite the tongue when it is at rest. In describing and classifying vowels the following parts of the tongue are referred to because of their great importance as resonance-modifiers: (1) the front of the tongue, which lies opposite the hard palate (in Russian phonetic literature it is called the middle of the tongue), (2) the back of the tongue, which lies opposite the soft palate (3) the centre of the tongue, which is the region where the front and the back meet. The tip and blade of the tongue do not play separate roles in vowel production. As the body, or bulk, of the tongue moves forward or backward, i.e. in a horizontal direction, one of the parts of its surface is usually higher than all the other parts, although its actual height from the lowest position and, therefore, the distance between this highest point and the opposite part of the roof of the mouth, may vary, thus marking the simultaneous movement of the tongue in a vertical direction.
This complex movement of the tongue provides a convenient articulatory basis for classifying vowels according to two important principles: (1) according to the horizontal (or, to be more exact, forward-backward) movement of the tongue, or, as D. Jones puts it “according to the part of the tongue which is raised highest” (2) according to the simultaneous vertical movement of the tongue or, as D. Jones puts it “according to the height to which the tongue is raised” These two main principles of vowel classification are generally accepted, although they may be, as we have seen, expressed in different ways, and there may be, as we shall see later, differences of opinion as to how many classes of vowels should be distinguished according to these principles, by what terms these classes should be designated and which vowels should be assigned to this or that class.
When the bulk of the tongue moves forward, it is usually its front part which is raised highest, towards the hard palate. Vowel sounds produced with this tongue position are called front vowels, e.g. the English [i:, i, e, ae] and the nuclei of the English diphthongs [ta, ei, ea, ai, au]. The English front vowels [i:] and [i] actually differ from each other not only in length, but also in quality. One of the causes of the latter difference is the difference in the parts of the tongue which are raised highest in pronouncing [i:] and [i]. In the case of [i:] the highest part of the tongue is defined by D. Jones as the centre of the front, whereas in the case of [i] it is defined by him as the hinder part of the front. This difference in tongue position necessitates the subdivision of the English front vowels into fully front ([i:, e, ae] and the nuclei of [ei, ea, ai]) and front-retracted ([i] and the nucleus of [au]). This subdivision is especially necessary since the vowels [i:] and [i] represent different phonemes in English mainly because of a difference in quality and not in quantity (although D. Jones considers them variants of one phoneme, both of which he designates by the symbol i). The term front vowels are rather misleading because it is not the front of the tongue that is directly responsible for their production. As a matter of fact, they are produced by the action of the mouth resonator which is divided into two parts by the raised front of the tongue, and the higher it is raised, the larger is the empty space left in the back part of the mouth cavity and the greater is the role of this back resonator in producing front vowels. When the bulk of the tongue moves backwards, it is usually its back part which is raised highest, towards the soft palate. Vowel sounds produced with this tongue position are called back vowels, e.g. the English [a:, o, o:, u:, u, A] and the nuclei of [ aa, ou, ua], as well as the Russian [o, y]. The English back vowels [u:] and [is], like [i:] and [i], actually differ from each other not only in length, but also in quality. As in the case of [i:] and [i], one of the causes of this qualitative difference is the difference in the parts of the tongue which are raised highest in pronouncing [u:] and [u]. In the case of [u:] the highest part of the tongue is defined by D. Jones as the back, whereas in the case of [«] it is defined by him as the fore part of the back.
This difference in tongue position necessitates the subdivision of the English back vowels into fully back ([d, d:, u:]) and back-advanced, [a:, A, U] and the nuclei of the diphthongs ou, ua]). This subdivision is especially necessary since the vowels [u:] and [15] represent different phonemes in English mainly because of a difference in quality and not in quantity. Authorities differ as to which of the two subclasses of the English back vowels the principal variant of the phoneme /a:/ and the nucleus of the diphthong [ou] should be assigned. G. P. Torsuyev assigns [a:] to the subclass of fully back vowels, whereas A. L. Trakhterov places it among back-advanced vowels. D. Jones defines the part of the tongue which is raised highest as “a point somewhat in advance of the centre of the back” in pronouncing [a:], and as “the back”. From a phonological point of view there is also more reason to regard [a:] as a backadvanced vowel. The nucleus of the diphthong [ou] is traditionally defined as a back-advanced vowel, but the authors of some of the latest works on English phonetics, for instance, A. C. Gim- son regard it as a variety of the neutral vowel and designate the diphthong by the symbol [au]. This is, probably, too bold a departure from the tradition, considering that in the pronunciation of many RP speakers there is just the opposite tendency, viz., to pronounce the nucleus of the diphthong [ou] as a fully back vowel approximating in quality to the Russian [o], but this is rather convenient from a pedagogical point of view. Although we speak of back vowels, it should be borne in mind that they are actually produced mainly by the action of the resonator in the front part of the mouth cavity since it is there that an empty space is formed as the result of raising the back part of the tongue. When the centre of the tongue is raised towards the junction between the hard and soft parts of the palate, vowels are produced which are called central, e.g. the Russian [a]. British phoneticians consider the English vowels [a] and [a:] also as central. Thus, D. Jones defines the part of the tongue which is raised highest in pronouncing [3:] as “the central part culminating at the junction between “front” and “back” He also regards [3:] and [a] as variants of one phoneme both of which he designates by the symbol a. Thus further investigations are apparently necessary to resolve this moot point.
The classification of the English vowels according to the vertical movement of the tongue worked out by Soviet phoneticians is also different from the traditional classifications by British and American phoneticians. Applied to RP English, the above classifications (both British and American) suffer from one serious drawback: they do not reflect the qualitative differences between the vowels in the pairs [i: — i], [u: — u], [d — a:], [a — a:] since both vowels are placed in one class. But these differences are extremely important, because it is due to their qualitative differences, and not quantitative ones, that the vowels in the above pairs function as different phonemes in RP English. True, D. Jones himself considers the vowels in the above pairs as variants of one and the same phoneme and thus ignores the distinctive relevance of their qualitative differences, but most of his British colleages do not share his opinion and consider those vowels as different phonemes; and yet they accept Jones’ classification. In order to eliminate this shortcoming Soviet phoneticians have elaborated a more exact classification. In it the English vowels are first divided into three classes according to the three main heights of the tongue: (1) high, or c/ose, vowels; (2) mid or half-open, vowels, and (3) low, or open, vowels. Then each of these three classes is further divided into two subclasses according to the two variations of the three main tongue-heights; (a) vowels of the narrow variation, (b) vowels of the broad variation.
P. Torsuyev and A. L. Trakhterov differ in classifying the principal variant of the [a]-phoneme according to the height of the tongue: the former places it among mid-broad vowels, i.e. together with [a], while the latter assigns it to lownarrow vowels, together with [o:]. D. Jones places [a], in his vowel chart, below [a], but above [o:], right on the border line between half-open and open vowels and defines it as half-open. Since both decisions are possible without violating linguistic reality, it is preferable, from the viewpoint of structural symmetry, to assign the English /A/-phoneme to low-narrow vowels because that would bring out the same relationship between the vowel phonemes in the pairs /i: — i/, /u: — is/, h:—a/, /a:—a/, /d: — d/, viz., that they belong to the same class according to the three main heights of the tongue, but to two different subclasses of the same class according to the variation of tongue-height.
Another common feature is that, with the exception of /a — a:/, the historically long vowels belong to the narrow variety, whereas the historically short vowels belong to the broad variety within one and the same class.

Chapter II. English vowel phonemes in connected speech.

2.1. Modifications of Vowels in Connected Speech

While learning modification of the vowel phonemes I came across different approaches to the modification of vowels and their scientific problems in learning and some of them we have discussed below. The modifications of vowels in a speech chain are traced in the following directions: they are either quantitative or qualitative or both. These changes of vowels in a speech continuum are determined by a number of factors such as the position of the vowel in the word, accentual structure, tempo of speech, rhythm, etc.The decrease of the vowel quantity or in other words the shortening of the vowel length is known as a quantitative modification of vowels, which may be illustrated as follows: 1. The shortening of the vowel length occurs in unstressed positions, e.g. blackboard [ɔ:], sorrow [зu] (reduction). In these cases reduction affects both the length of the unstressed vowels and their quality. Form words often demonstrate quantitative reduction in unstressed positions, e.g. Is →he or she to blame? ̖– [hi:] But: At → last he has come ̖. – [hi] 2. The length of a vowel depends on its position in a word. It varies in different phonetic environments. English vowels are said to have positional length, e.g. knee – need – neat (accommodation).
The vowel [i:] is the longest in the final position, it is obviously shorter before the lenis voiced consonant [d], and it is the shortest before the fortis voiceless consonant [t]. Qualitative modification of most vowels occurs in unstressed positions. Unstressed vowels lose their "colour", their quality, which is illustrated by the examples below: 1. In unstressed syllables vowels of full value are usually subjected to qualitative changes, e.g. man [mæn] – sportsman ['spɔ:tsmən], conduct ['kɒndəkt] – conduct [kən'd٨kt]. In such cases the quality of the vowel is reduced to the neutral sound [ə]. These examples illustrate the neutralized (reduced) allophones of the same phonemes as the same morphemes are opposed. Nearly one sound in five is either [ə] or the unstressed [i]. This high frequency of [ə] is the result of the rhythmic pattern: if unstressed syllables are given only a short duration, the vowel in them which might be otherwise full is reduced. It is common knowledge that English rhythm prefers a pattern in which stressed syllables alternate with unstressed ones. The effect of this can be seen even in single words, where a shift of stress is often accompanied by a change of vowel quality; a full vowel becomes [ə], and [ə] becomes a full vowel.
Compare: analyse ['ænəlaiz] – analysis [ə'nælisis]. 2. Slight degree of nasalization marks vowels preceded or followed by the nasal consonants [n], [m], e.g. never, no, then, men (accommodation). The realization of reduction as well as assimilation and accommodation is connected with the style of speech. In rapid colloquial speech reduction may result in vowel elision, the complete omission of the unstressed vowel, which is also known as zero reduction. Zero reduction is likely to occur in a sequence of unstressed syllables, e.g. history, factory, literature, territory. It often occurs in initial unstressed syllables preceding the stressed one, e.g. correct, believe, suppose, perhaps. The example below illustrates a stage-by-stage reduction (including zero reduction) of a phrase. Has he done it? [hæz hi· ,d٨n it] [həz hI ,d٨n it] [əz i ,d٨n it] [z i ,d٨n it] 3. Sound Alternations The sound variations in words, their derivatives and grammatical forms of words are known as sound alternations. It is perfectly obvious that sound alternations are caused by assimilation, accommodation and reduction in speech. Alternations of consonants are mainly due to contextual assimilations: the dark [ł] in spell alternates with the clear [l] in spelling. Vowel alternations are the result of the reduction in unstressed positions: combine ['kɒmbain] (n) – combine [kəm'bain] (v) where [ɒ] in the stressed syllable of the noun alternates with the neutral sound in the unstressed syllable of the verb. Some sound alternations are traced to the phonetic changes in earlier periods of the language development and are known as historical. The following list of examples presents the most common types of historical alternations. 1. Vowel Alternations 1. Distinction of irregular verbal forms: [i: – e – e]: mean – meant – meant [i – ٨– ٨]: dig – dug – dug. [ai – зu – i]: write – wrote – written [i – æ – ٨] : sing – sang – sung [εə – ɔ: – ɔ:]: wear – wore – worn [ai – i – i]: hide – hid – hidden [i: – зu – зu]: speak – spoke – spoken [зu – u: – зu]: know – knew – known [i – ei – i]: give – gave – given [e – ɒ – ɒ]: get – got –got [i: – ɔ: – ɔ:]: teach – taught – taught [æ – u – u]: understand – understood – understood [ei – u – ei ]: take – took – taken [ei – зu – зu]; wake – woke – woken [u: – ɒ – ɒ]: shoot – shot – shot [e – зu – зu]: tell – told – told [i – æ – æ]: sit – sat – sat [i – ɔ: – ɔ:]: think – thought – thought [٨ – ei – ٨]: become – became – become [ai – зu – i]: rise – rose – risen [зu – u: – зu]: grow – grew – grown [u: – зu – зu]: choose – chose – chosen [ai – u: – зu]: fly – flew – flown [ai – ɔ: – ɔ:]: fight – fought – fought [ai – au – au]: find – found – found [i: – ɔ: – i:]: see – saw – seen [iə – з: – з:]: hear – heard – heard and some other less common verbal alternations of this type. 2. Distinction of causal verbal forms: [i – e]: sit – set [ai – ei]: rise – raise [ɔ: – e] fall – fell 3. Distinction of singular and plural forms of nouns: [æ – e]: man – men [u – i:]: foot – feet [u: – i:]: tooth – teeth [au – ai]: mouse – mice [u – i]: woman – women [ai – i]: child – children 4. Distinction of parts of speech in etymologically correlated words: [i: – e]: feast – festive [a: – æ]: class – classify [ɒ – e]: long – length [ɔ: – e]: broad – breadth [ei – æ]: nation – national [ai – i]: wise – wisdom [ɒ – i:]: hot – heat This type of alternation is often strengthened not only by suffixation but also by the shifting of stress like in: part– particular, 'climate – cli'matic.53 2. Consonant Alternations 1. Distinction of irregular verbal forms: [d – t]: send – sent, lend – lent 2. Distinction of parts of speech in etymologically correlated words: [s – z]: advice – advise, house – house, use – use [s – d]: defence – defend [t – d]: intent – intend [k – t ∫]: speak – speech [t – s]: important – importance 3. Vowel + Consonant Alternations (often supported by suffixation and the shifting of stress) [i – ai] + [v – f]: live – life [a: – ei] + [θ – ð]: bath – bathe [e – i:] + [θ – ð]: breath – breathe [ɒ – u:] + [s – z]: loss – lose Sound alternations are also widely spread on the synchronical level in the presentday English and are known as contextual. In connection with contextual sound alternations there arises a problem of phonemic identification of alternated sounds. The functioning of sounds in different grammatical forms and derivatives of words seems very complicated and flexible. The study of the relationship between phonemes and morphemes is called morphophonemics. The interrelation of phonology and morphology in linguistic investigations is also known as morphophonology or morphonology which is actually the phonology of morphemes. Morphonology studies the way in which sounds can alternate as different realizations of one and the same morpheme. A morpheme is a minimal unit of meaning. We would all agree that such words as windy, dusty, sunny consist of two morphemes. Similarly, demonstration, alternation have two component morphemes.
The meanings of wind, dust, sun as well as of demonstrate, situate are obvious. But what function do the morphemes -y and -ion perform? On the basis of the examples, it appears that the function of -y is to convert a noun into an adjective. Similarly -ion converts a verb into a noun. These morphemes have a grammatical meaning, their main purpose is to convert one part of speech into another. Each set of data below exemplifies a sound alternation in one and the same morpheme of two different parts of speech. malice ['mælis] – malicious [mə'li∫əs] active ['æktiv] – activity [ək'tiviti] abstract ['aæbstrækt] – abstract [æb'strækt] conduct ['k ɒ ndəkt] – conduct [kən'd٨kt] contrast ['k ɒ ntræst] – contrast [kən'træst] We are interested now in the sound in its weak position. Vowels are said to be in their strong position when they are in stressed syllables and in the weak position when they are in the unstressed ones. Consonants may well be said to be in their strong position before vowels and in the intervocalic position; they are in weak positions when they are word final or precede other consonants. There may be different solutions to the problem of phoneme identification in weak positions of alternated words. The question arises whether the sound [ə] in the words activity and con'trast is a neutral phoneme or it is an allophone of the [æ] or [ɒ] phonemes (as in active, 'contrast) which loses some of its distinctive features in the unstressed position. The difference is quite essential as in the first case the neutral sound is identified as an independent neutral phoneme, in the second – it is a neutralized allophone of the [æ] or [ɒ] phonemes of the corresponding alternated words. The loss of one or more distinctive features of a phoneme in the weak position is called phonemic neutralization. In English, the voicing opposition is neutralized after the initial [s]. We are well aware of the fact that the phonemes [t] and [d], for example, contrast in most environments: initially (tick —Dick), finally (bid – bit); after nasals (bend – bent), after [l] (cold – colt). But after [s], no contrast between [t], [d] is possible, nor, similarly, is there a contrast between [p], [b] and [k], [g] in this environment. The voicing contrast is neutralized after initial [s].

2.2. Changes of the vowel phonemes in connected speech

This chapter is devoted to the Changes of the vowel phonemes in connected speech. So we will try to investigate by some active methods. So far we have given a lot of attention to the classification of vowels. Vowels as units of system of sounds were analyzed as if pronounced in the stressed position in the word. At this point we should discus characteristics of vowels in the unstressed position in the word. It is well-known that a vowel in the unstressed position is short, weak and undistinguished. Unstressed vowels are usually associated with: among [əmo:ŋ] before [bif ɔ:] useful [ju:zful] tomato [təmətəu] exercise [eksəsaz] sudden [sədən] Also vowels of full quality sometimes appear in unstressed positions. It happens in borrowed words of Latin and Greek origin: architect [ə:kitekt], paragraph [pærəra:f], canteen [kænti:n]. The phonemic status of the neutral sound [ə]. At this point we should discuss the phonemic status of the neutral sound [ə]. The phonological analysis is made with the help of oppositions of the words. If sounds (two variants of one sound) change the meaning of the words then a sound is a separate phoneme: officers – offices accept – except armour – army In these examples the neutral sound [ə] is opposite to the phoneme [i] It differentiates the meaning of the words so in these examples [ə] is a separate phoneme. But there are some other examples: man – businessman board – blackboard post – postpone These sounds are allophones of one and the same phoneme [ə]. In discussing vowels we should turn to vowel reduction. The modifications of vowels in speech are traced in the following directions: quantitative, qualitative or both these changes of vowels of speech are determined by many factors:
1. position in the word
2. accentual structure
3. tempo of speech
4. rhythm and so on The decrease of the vowels quantity (shortening of the vowels length) is known as quantitative modification of vowels and can illustrated as follows: 1) the shortening of vowel occurs in the unstressed position: board - blackboard In this case reduction affects the quantity and the quality of the vowel. 2) the length of the vowel depends on its position of the word: knee [i:] – need – neat It is only quantitative change. Unstressed vowels lose their quality: 1) in unstressed syllables man –sportsman conduct [kəndakt] – conduct [kəndəkt] The neutral sound [ə] is the most frequent sound of English: about 11% of all English sounds, in combination with [ə] – about 20%. 2) slight degree of nasalization occurs when a vowel is followed or preceded by nasal consonants [m] [n]: never – no – then – man The relation of reduction as well as assimilation and accommodation is greatly connected with the style of speech. In colloquial speech reduction may even result in vowel elision. history – factory – literature – territory – correct – believe – suppose – perhaps Sound alternations In the previous section we saw how the pronunciation of sounds can vary according to the position in the word and this change is quite regular. These changes are very predictable. Now we’ll discuss different modifications of sounds which don’t depend on assimilation or accommodation due to position in the word but depend on some greater factors: Some sound alternations depend on the history of English and are called historical. The influence both vowels and consonants: Vowel alternations Changes of irregular verbal forms:
1. [i:-e-e] feed-fed-fed
2. [i- ɔ - ɔ] win-won-won
3. z[ai- ɔ u-i] write-wrote-written
4. [i-æ-a:] begin-began-begun
5. [iə- ɔ:- ɔ:] wear-wore-worn
6. [ai-i-i] hide-hid-hidden
7. [i:- ɔ u- ɔ u] steal-stole-stolen
8. [ou-u:-ou] blow-blew-blown
9. [i-ei-i] give-gave-given
10. [e-ɔ - ɔ] get-got-got
11. [i:- ɔ:- ɔ:t ] teach-taught-taught
12. [i-e- ɔ:] become-became-become
13. [ai-ou- i ] rise-rose-risen
14. [u:-ou-ou] choose-chose-chosen
15. [ai-u:- ɔ u] fly-flew-flown
16. [aə- ɔ:- ɔ:] fight-fought-fought
17. [ai-au-au] find-found-found
18. [i:- ɔ:- i:] see-saw-seen
19. [iə-a:-a:] hear-heard-heard
Changes of verbal forms: [i-e] sit-set [ai-ei] rise Changes of singular and plural forms of nouns: [æ-e] man-men [u-i:] foot-feet [u:-i:] tooth-teeth [au-ai] mouse-mice [u-i] woman-women [ai-i] child-children Changes of parts of speech in etymologically connection speech: [i:-e] feast-festive [ə:-æ] class-classify [ɔ:-e] long-length [ɔ:-e] broad-breadth [ei-æ] nation-national [ai-i] wise-wisdom [ɔ:-i:] hot-heat Consonant alternations Changes of irregular verbs: [d-t] send-sent Changes of part of speech in etymologically connected words: [s-z] advise (n)-advise (v); house (n)-house (v); use (n)-use (v) [s-d] defence-defend [t-d] intent-intend [k-t] sreak-speech [t-s] important-importance Vowel + consonant alternations [ɪ-ai] + [v-f] live-life [a:-e] + [θ-ð] bath-bathe [e-i:] + [θ-ð] breath-breathe [ɔ-u:] + [s-z] loss-lose In the Russian language there numerous types of vowel + consonant alternations: сидеть – сядь – сел – сажать плыть – пловец – сплав судить – сужу резать – режу лететь – лечу плакать – плачу Except historical sound alternations can also be modern and known as contextual. They depend on the style of speech, the tempo of speech and the situation.

Conclusion

The research made in the nature of English vowel phonemes shows that vowels have no special place of articulation, the whole of the speech apparatus takes part in producing them. The classification of vowels, as well as the description of their articulation, is therefore based upon the work of all the speech organs. We know that allophones of each phoneme possess a bundle of distinctive features, that makes this phoneme functionally different from all other phonemes of the language. This functionally relevant bundle of articulatory features is called the invariant of the phoneme. The analysis also found out that the definitions of the phoneme given by different linguistic scholars vary greatly. Here are some of them: L.V.Shcherba: the phoneme may be viewed as a functional, material and abstract unit [11.142]. V.A.Vassilyev: The phoneme is a smallest unit capable of distinguishing one word from another word, one grammatical form of word from another[30.124]. Bloch: phoneme is a class of phonemically similar sounds contrasting and mutually exclusive with all similar classes in the language Jacobson: phoneme is a minimal sound by which meaning may be discriminated. Before getting down to the analysis of the vowel system of English we tried to find out characteristic features of English vowel phonemes: 1. The phoneme is a functional unit. Function is usually understood to mean discriminatory function, that is, the role of the various components of the phonetic system of the language in distinguishing one morpheme from another, one word from another or also one utterance from another. The opposition of phonemes in the same phonetic environment differentiates the meaning of morphemes and words, e.g. said— says, sleeper — sleepy, bath — path, light — like.

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