Theoretical phonetics

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Introduction

Spoken language communication is arguably the most important activity that distinguishes humans from non-human species. While many animal species communicate and exchange information using sound, humans are unique in the complexity of the information that can be conveyed using speech, and in the range of ideas, thoughts and emotions that can be expressed.

This presentation provides an overview of the review papers that make up this theme issue on the processes underlying speech communication. The volume includes contributions from researchers who specialize in a wide range of topics within the general area of speech perception and language processing.

This work consists of two main parts with their subtitles where the detailed information about speech sounds in English is given.

In this presentation we tried to cover the general information referring to phonemic structure and functions of every speech sound in English, mention the main characteristics, aspects, notation of the latest. We used the several classifications and points of view of some Russian and British phoneticians, brought the examples in order to make the information more understandable. In addition we mention the main trends in Phonemic theory which was founded by the Russian scientist Boudoin-de-Courtenay who was the head of the Kazan Linguistic School. He defined the phoneme as a physical image of a sound. He also regarded phonemes as fictitious units and considered them to be only perceptions.

Language in everyday use is not conducted in terms of isolated, separate units; it is performed in connected sequences of larger units, in words, phrases and longer utterances. And there are actually some remarkable differences between the pronunciation of a word in isolation and of the same word in a block of connected speech. Though these changes are mostly quite regular and predictable, there is still problem of defining the phonemic status of sounds in connected speech. It happens because of the numerous modifications of sound in speech. These modifications are observed both within words and at word boundaries. The next part describes these modifications either.

Some scholars consider that frequency of occurrence of phonemes and phonemic clusters may be a factor of stability in language in the sense that frequent phonemes resist modifications and modify the rare one. That is why the methods of phonological analysis are found a place in this work.

The main part of this presentation consists of the modifications of Consonants in Connected Speech, the articulatory classification of English consonants and the articulatory classification of English vowels. There are different classifications according to the different scholars phoneticians - both Russian and British, as well as American, which we describe here.

phonemic theory sound speech



Part 1

Whereas phonetics is the study of sounds and is concerned with the production, audition and perception of speech sounds (called phones), phonology describes the way sounds function within a given language and operates at the level of sound systems and abstract sound units. Knowing the sounds of a language is only a small part of phonology. This importance is shown by the fact that you can change one word into another by simply changing one sound.

1.1 Aspects of Speech Sounds

Speech sounds are 1) produced by man's organs of speech, 2) travel in sound waves, and 3) are perceived by man's hearing mechanism as 4) sounds of language functioning as units capable of differentiating meanings of the words. It follows that speech sounds differ from each other in their physical/acoustic properties, in the way they are produced by the organs of speech and in their features which take part or do not take part in differentiating the meaning, i.e. it will be possible to distinguish the following four aspects: 1) articulatory 2) acoustic 3) auditory 4) functional (linguistic, social) of speech sounds.

Neither of them can be separated in the actual process of communication (in the flow of speech). Each of them can be singled out for linguistic analysis.

The articulatory/sound production aspect: from the articulatory point of view every speech sound is a complex of definite coordinated and differentiated movements and positions of speech organs. The movements and positions necessary for the production of a speech sound constitute its articulation.

The acoustic aspect: every speech sound is a complex of acoustic effects and has its Physical properties - it is a physical phenomenon, a kind of moving matter and energy. The Physical (acoustic) properties of speech sounds consist of: 1) frequency, 2) spectrum, 3) intensity, 4) duration.

The auditory/sound-perception aspect involves the mechanism of hearing. It is a kind of psychological mechanism which (I) reacts to the physical properties of speech sounds, (II) selecting from a great amount of information only the one which is linguistically relevant.

The functional/linguistic/social aspect is called so because of the role the sounds of language play in its functioning as medium of human communication.

1.2 General Characteristics of Phonemes

When we talk about the sounds of a language, the term "sound" can be interpreted in two rather different ways. A linguist uses two separate terms: "phoneme" is used to mean "sound" in its contrastive sense, e.g.: tie -- die, seat -- seed and "allophone" is used for sounds which are variants of a phoneme. They usually occur in different positions in the word (i.e. in different environments) and hence cannot contrast with each other, nor be used to make meaningful distinctions.

V.A.Vassilyev defined the phoneme like this:

The segmental phoneme is the smallest (i.e. further indivisible into smaller consecutive segments) language unit (sound type) that exists in the speech of all the members of a given language community as such speech sounds which are capable of distinguishing one word of the same language or one grammatical form of a word from another grammatical form of the same word" (Vassilyev 1970: 136).

The only drawback of this definition is that it is too long and complicated for practical use. The concise form of it could be:

The phoneme is a minimal abstract linguistic unit realized in speech in the form of speech sounds opposable to other phonemes of the same language to distinguish the meaning of morphemes and words [Теоретическая фонетика 1996: 40].

Let us consider the phoneme from the point of view of its three aspects. Firstly, 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.

Sometimes the opposition of phonemes serves to distinguish the meaning of the whole phrases, e.g. He was heard badly - He was hurt badly. Thus we may say that the phoneme can fulfil the distinctive function.

Secondly, the phoneme is material, real and objective. That means that it is realized in speech of all English-speaking people in the form of speech sounds, its allophones.

The sets of speech sounds, that is the allophones belonging to the same phoneme are not identical in their articulatory content though there remains some phonetic similarity between them.

As a first example, let us consider the English phoneme [d], which when not affected by the articulation of the preceding or following sounds is a plosive, fore-lingual apical, alveolar, lenis stop. This is how it sounds in isolation or in such words as door, darn, down, etc., when it retains its typical articulatory characteristics. In this case the consonant [d] is called the principal allophone. At the same time there are quite predictable changes in the articulation of allophones that occur under the influence of the neighbouring sounds in different phonetic situations. Such allophones are called subsidiary.

[d] is slightly palatalized before front vowels and the sonorant [j], e.g. deal, day, did, did you.

[d] is pronounced without any plosion before another stop, e.g. bedtime, bad pain, good dog; it is pronounced with the nasal plosion before the nasal sonorants [n] and [m], e.g. sudden, admit, could not, could meet; the plosion is lateral before the lateral sonorant [l], e.g. middle, badly, bad light.

Followed by [r] the consonant [d] becomes post-alveolar, e.g. dry, dream; followed by the interdental [и], [р] it becomes dental, e.g. breadth, lead the way, good thing.

When [d] is followed by the labial [w] it becomes labialized, e.g. dweller.

In the initial position [d] is partially devoiced, e.g. dog, dean; in the intervocalic position or when followed by a sonorant it is fully voiced, e.g. order, leader, driver; in the word-final position it is voiceless, e.g. road, raised old.

Allophones are arranged into functionally similar groups, that is groups of sounds in which the members of each group are not opposed to one another, but are opposable to members of any other group to distinguish meanings in otherwise similar sequences. But the phones which are realized in speech do not correspond exactly to the allophone predicted by this or that phonetic environment. They are modified by phonostylistic, dialectal and individual factors. In fact, ho speech sounds are absolutely alike.

Thirdly, allophones of the same phoneme, no matter how different their articulation may be, function as the same linguistic unit. The native speaker is quite readily aware of the phonemes of his language but much less aware of the allophones: it is possible, in fact, that he will not hear the difference between two allophones like the alveolar and dental consonants [d] in the words bread and breadth even when a distinction is pointed out; a certain amount of ear-training may be needed. The reason is that the phonemes differentiate words like tie and die from each other. Allophones, on the other hand, have no such function.

At the same time native speakers realize, quite subconsciously of course, that allophones of each phoneme possess a bundle of distinctive features, that makes this phoneme functionally different from all other phonemes of the language concerned. This functionally relevant bundle of articulatory features is called the invariant of the phoneme.

Neither of the articulatory features that form the invariant of the phoneme can be changed without affecting the meaning. All the allophones of the phoneme [d], for instance, are occlusive, forelingual, lenis. If occlusive articulation is changed for constrictive one [d] will be replaced by [z], cf. breed - breeze, deal - zeal; [d] will be replaced by [g] if the forelingual articulation is replaced by the backlingual one, cf. dear - gear, day - gay. The lenis articulation of [d] cannot be substituted by the fortis one because it will also bring about changes in meaning, cf. dry - try, ladder - latter, bid - bit.

The articulatory features which form the invariant of the phoneme are called distinctive or relevant. To extract a relevant feature of the phoneme we have to oppose it to some other phoneme in the same phonetic context. If opposed sounds differ in one articulatory feature and this difference brings about changes in the meaning of the words the contrasting features are called relevant. For example, the words port and court differ in one consonant only, that is the word port has the initial consonant [p], and the word court begins with [k]. Both sounds are occlusive and fortis, the only difference being that [p] is labial and [k] is backlingual. Therefore it is possible to say that labial and backlingual articulations are relevant in the system of English consonants.

The articulatory features which do not serve to distinguish meaning are called non-distinctive, irrelevant or redundant; for instance, it is impossible in English to oppose an aspirated [p] to a non-aspirated one in the same phonetic context to distinguish meanings.

That is why aspiration is a non-distinctive feature of English consonants.

If an allophone of some phoneme is replaced by an allophone of a different phoneme the mistake is called phonological, because the meaning of the word is inevitably affected, e.g.: beat - bit.

If an allophone of the phoneme is replaced by another allophone of the same phoneme the mistake is called phonetic. It happens when the invariant of the phoneme is not modified and consequently the meaning of the word is not affected, e.g.:

When the vowel [i:] is fully long in such a word as sheep, for instance, the quality of it remaining the same, the meaning of the word does not change.

Thirdly, the phoneme is abstract or generalized and that is reflected in its definition as a language unit. It is an abstraction because we make it abstract from concrete realizations for classificatory purposes.

1.3 Notation

The abstractional and material aspects of the phoneme have given rise to the appearance of transcription. Transcription is a set of symbols representing speech sounds.

The symbolization of sounds naturally differs according to whether the aim is to indicate the phoneme, i.e. a functional unit as a whole, or to reflect the modifications of its allophones as well.

The International Phonetic Association (IPA) has given accepted values to an inventory of symbols, mainly alphabetic but with additions. The first type of notation, the broad or phonemic transcription, provides special symbols for all the phonemes of a language.

The second type, the narrow or allophonic transcription, suggests special symbols including some information about articulatory activity of particular allophonic features.

The broad transcription is mainly used for practical expedience, the narrow type serves the purposes of research work. We shall discuss two kinds of broad transcription which are used for practical purposes in our country. The first type was introduced by D. Jones.

He realized the difference in quality as well as in quantity between the vowel sounds in the words sit and seat, pot and port, pull and pool, the neutral vowel and the vowel in the word earn.

According to D. Jones' notation English vowels are denoted like this: [i] - [i:], [e]

- [ж], [?] - [a:], [?] - [?:], [u] - [u:], [?] - [з:]. This way of notation disguises the qualitative difference between the vowels [I] and [i:], [?] and [?:], [u] and [u:], [?] and [з:] though nowadays most phoneticians agree that vowel length is not a distinctive feature of the vowel, but is rather dependent upon the phonetic context, that is it is definitely redundant. For example, in such word pairs as hit - heat, cock - cork, pull - pool the opposed vowels are approximately of the same length, the only difference between them lies in their quality which is therefore relevant.

The other type of broad transcription, first used by V.A. Vassilyev, causes no phonological misunderstanding providing special symbols for all vowel phonemes: [i], [i:], [e], [ж], [a:], [?], [?], [?:], [u], [u:], [?], [з:].

The narrow or phonetic transcription incorporates as much more phonetic information as the phonetician desires, or as he can distinguish. It provides special symbols to denote not only the phoneme as a language unit but also its allophonic modifications. The symbol [h] for instance indicates aspirated articulation, cf. [kheit] - [skeit].

1.4 Main Trends in Phoneme Theory

Views of the phoneme seem to fall into four main classes. The "mentalistic" or "psychological" view regards the phoneme as an ideal "mental image" or a target at which the speaker aims. He deviates from this ideal sound partly because an identical repetition of a sound is next to impossible and partly because of the influence exerted by neighbouring sounds. According to this conception allophones of the phoneme are varying materializations of it. This view was originated by the founder of the phoneme theory, the Russian linguist I.A. Baudouin de Courtenay and something like it appears to have been adopted by E.D. Sapir, Alf. Sommerfelt , M. Tatham.

The so-called "functional" view regards the phoneme as the minimal sound unit by which meanings may be differentiated without much regard to actually pronounced speech sounds. Meaning differentiation is taken to be a defining characteristic of phonemes.

Thus the absence of palatalization in [l] and palatalization of the dark [і] in English do not differentiate meanings, and therefore [l] and [і] cannot be assigned to different phonemes but both form allophones of the phoneme [l]. This view is shared by many foreign linguists: see in particular the works of N. Trubetskoy, L. Bloomfield, R. Jakobson, M. Halle.

The functional view of the phoneme gave rise to a branch of linguistics called "phonology" or "phonemics" which is concerned with relationships between contrasting sounds in a language. Its special interest lies in establishing the system of distinctive features of the language concerned. Phonetics is limited in this case with the precise description of acoustic and physiological aspects of physical sounds without any concern to their linguistic function.

A stronger form of the "functional" approach is advocated in the so-called "abstract" view of the phoneme, which regards phonemes as essentially independent of the acoustic and physiological properties associated with them, that is of speech sounds. This view of the phoneme was pioneered by L. Hjelmslev and his associates in the Copenhagen Linguistic Circle, H.J. Uldall and K. Togby.

The views of the phoneme discussed above can be qualified as idealistic since all of them regard the phoneme as an abstract conception existing in the mind but not in the reality, that is in human speech, speech sounds being only phonetic manifestations of these conceptions.

The "physical" view regards the phoneme as a "family" of related sounds satisfying certain conditions, notably:

1. The various members of the "family" must show phonetic similarity to one another, in other words be related in character.

2. No member of the "family" may occur in the same phonetic context as any other.

The extreme form of the "physical" conception, as propounded by D. Jones and shared by B. Bloch and G. Trager, excludes all reference to non-articulatory criteria in the grouping of sounds into phonemes.



1.5 Methods of Phonological Analysis

The aim of the phonological analysis is, firstly, to determine which differences of sounds are phonemic (i.e. relevant for the differentiation of the phonemes) and which are non-phonemic and, secondly, to find the inventory of the phonemes of this or that language.

A number of principles have been established for ascertaining the phonemic structure of a language. For an unknown language the procedure of identifying the phonemes of a language as the smallest language units has several stages. The first step is to determine the minimum recurrent segments (segmentation of speech continuum) and to record them graphically by means of allophonic transcription. To do this an analyst gathers a number of sound sequences with different meanings and compares them. For example, the comparison of [stik] and [stжk] reveals the segments (sounds) [i] and [ж], comparison of [stik] and [spik] reveals the segments [st] and [sp] and the further comparison of these two with [tIk] and [taek], [sik] and [sжk] splits these segments into smaller segments [s], [t], [p]. If we try to divide them further there is no comparison that allows us to divide [s] or [t] or [p] into two, and we have therefore arrived at the minimal segments. From what we have shown it follows that it is possible to single out the minimal segments opposing them to one another in the same phonetic context or, in other words, in sequences which differ in one element only.

The next step in the procedure is the arranging of sounds into functionally similar groups. We do not know yet what sounds are contrastive in this language and what sounds are merely allophones of one and the same phoneme. There are two most widely used methods of finding it out. They are the distributional method and the semantic method. The distributional method is mainly used by phoneticians of "structuralist" persuasions.

These phoneticians consider it to group all the sounds pronounced by native speakers into phonemes according to the two laws of phonemic and allophonic distribution.

These laws were discovered long ago and are as follows.

1. Allophones of different phonemes occur in the same phonetic context.

2. Allophones of the same phoneme never occur in the same phonetic context.

The fact is that the sounds of a language combine according to a certain pattern characteristic of this language. Phonemic opposability depends on the way the phonemes are distributed in their occurrence. That means that in any language certain sounds do not occur in certain positions.

If more or less different sounds occur in the same phonetic context they should be allophones of different phonemes. In this case their distribution is contrastive.

If more or less similar speech sounds occur in different positions and never occur in the same phonetic context they are allophones of one and the same phoneme. In this case their distribution is complementary.

Still there are cases when two sounds are in complementary distribution but are not referred to the same phoneme. This is the case with the English [h] and [n]. [h] occurs only initially or before a vowel while [n] occurs only medially or finally after a vowel and never occurs initially. In such case the method of distribution is modified by addition of the criterion of phonetic similarity/ dissimilarity. The decisions are not made purely on distributional grounds. Articulatory features are taken into account as well.

So far we have considered cases when the distribution of sounds was either contrastive or complementary. There is, however, a third possibility, namely, that the sounds both occur in a language but the speakers are inconsistent in the way they use them. In such cases we must take them as free variants of a single phoneme. We could explain it on the basis of "dialect" or on the basis of sociolinguistics. It could be that one variant is a "prestige" form which the speaker uses when he is constantly "monitoring" what he says while the other variant of pronunciation is found in casual or less formal speech.

The semantic method. It is applied for phonological analysis of both unknown languages and languages already described. In case of the latter it is used to determine the phonemic status of sounds which are not easily identified from phonological point of view. The method is based on a phonemic rule that phonemes can distinguish words and morphemes when opposed to one another. The semantic method of identifying the phonemes of a language attaches great significance to meaning. It consists in systematic substitution of the sound for another in order to ascertain in which cases where the phonetic context remains the same such substitution leads to a change of meaning. It is with the help of an informant that the change of meaning is stated. This procedure is called the commutation test. It consists in finding minimal pairs of words and their grammatical forms. For example, an analyst arrives at the sequence [pin]. He substitutes the sound [p] for the sound [b] or [s], [d], [w]. The substitution leads to the change of meaning, cf.: pin, bin, sin, din, win. This would be a strong evidence that [p], [b], [s], [d], [w] can be regarded as allophones of different phonemes.

To establish the phonemic structure of a language it is necessary to establish the whole system of oppositions. All the sounds should be opposed in word-initial, wordmedial and word-final positions. There are three kinds of oppositions. If members of the opposition differ in one feature the opposition is said to be single, e.g. pen - ben. Common features: occlusive - occlusive, labial - labial. Differentiating feature: fortis - lenis.

If two distinctive features are marked, the opposition is said to be double, e.g. pen - den. Common features: occlusive - occlusive. Differentiating features: labial - lingual, fortis voiceless - lenis voiced.

If three distinctive features are marked the opposition is said to be triple, e.g. pen - then. Differentiating features: occlusive - constrictive, labial - dental, fortis voiceless - lenis voiced.



Part 2

2.1 The System of English Phonemes. Consonants

If speech sounds are studied from the point of view of their production by man's organs of speech, it is the differences and similarities of their articulation that are in the focus of attention. A speech sound is produced as a result of definite coordinated movements and positions of speech organs, so the articulation of a sound consists of a set of articulatory features.

Grouping speech sounds according to their major articulatory features is called an articulatory classification.

According to the specific character of the work of the speech organs, sounds in practically all the languages are subdivided into two major subtypes: VOWELS (V) and CONSONANTS (C).

There are 1) articulatory, 2) acoustic and 3) functional differences between V and C.

1. The most substantial articulatory difference between vowels and consonants is that in the articulation of V the air passes freely through the mouth cavity, while in making C an obstruction is formed in the mouth cavity and the airflow exhaled from the lungs meets a narrowing or a complete obstruction formed by the speech organs.

2. Consonants articulations are relatively easy to feel, and as a result are most conveniently described in terms of PLACE and MANNER of articulation.

3. Vowels have no place of obstruction, the whole of speech apparatus takes place in their formation, while the articulation of consonants can be localized, an obstruction or narrowing for each C is made in a definite place of the speech apparatus.

4. The particular quality of Vs depends on the volume and shape of the mouth resonator, as well as on the shape and the size of the resonator opening. The mouth resonator is changed by the movements of the tongue and the lips.

5. The particular quality of Cs depends on the kind of noise that results when the tongue or the lips obstruct the air passage. The kind of noise produced depends in its turn on the type of obstruction, on the shape and the type of the narrowing. The vocal cords also determine the quality of consonants.

6. From the acoustic point of view, vowels are called the sounds of voice, they have high acoustic energy, consonants are the sounds of noise which have low acoustic energy.

7. Functional differences between Vs and Cs are defined by their role in syllable formation: Vs are syllable forming elements, Cs are units which function at the margins of syllables, either singly or in clusters.

These differences make it logical to consider each class of sounds independently.

As it follows from the above given considerations, the sounds of a language can be classified in different ways. H. Giegerich [1992], M. Pennington [1996], use a set of basic binary (two-way) distinctions in terms of: 1) phonation; 2) oro-nasal process; 3) manner of articulation.

Thus, in accordance with the above-given grouping of sounds, the sounds of English an be classified as follows:



2.2 General Characteristics of Consonants

There are few ways of classifying English consonants. According to V.A.Vassilyev primary importance should be given to the type of obstruction and the manner of production of noise. On this ground he distinguishes two large classes of consonants:

1. occlusive, in the production of which a complete obstruction is formed;

2. constrictive, in the production of which an incomplete obstruction is formed.

The phonological relevance of this feature could be exemplified in the following oppositions:

[ti] - [si] tea - sea (occlusive - constrictive)

[si:d] - [si:z] seed - seas (occlusive - constrictive)

[pul] - [ful] pull - full (occlusive --constrictive)

[b?ut] - [v?ut] boat - vote (occlusive --constrictive)

Each of the two classes is subdivided into noise consonants and sonorants. The division is based on the factor of prevailing either noise or tone component in the auditory characteristic of a sound. In their turn noise consonants are divided into plosive consonants (or stops) and affricates.

Another point of view is shared by M.A. Sokolova, K.P. Gintovt, G.S. Tikhonova, R.M. Tikhonova. They suggest that the first and basic principle of classification should be the degree of noise. Such consideration leads to dividing English consonants into two general kinds: noise consonants and sonorants. Sonorants are sounds that differ greatly from all other consonants of the language.

This is largely due to the fact that in their production the air passage between the two organs of speech is fairly wide, that is much wider than in the production of noise consonants.

As a result, the auditory effect is tone, not noise. This peculiarity of articulation makes sonorants sound more like vowels than consonants. On this ground some of the British phoneticians refer some of these consonants to the class of semivowels, [r], [j], [w], for example. Acoustically sonorants are opposed to all other consonants because they are characterized by sharply defined formant structure and the total energy of most of them is very high. However, on functional grounds, according to their position in the syllable, [r], [j], [w] are included in the consonantal category, but from the point of view of their phonetic description they are more perfectly treated as vowel glides.

The place of articulation is another characteristic of English consonants which should be considered from the phonological point of view. The place of articulation is determined by the active organ of speech against the point of articulation. According to this principle the English consonants are classed into: labial, lingual, glottal. The class of labial consonants is subdivided into: a) bilabial; b) labio-dental; and among the class of lingual consonants three subclasses are distinguished; they are: a) forelingual, b) mediolingual and c) backlingual.

The importance of this characteristic as phonologically relevant could be proved by means of a simple example. In the system of English consonants there could be found oppositions based on the active organ of speech and the place of obstruction.

[pжn] - [taen] pan - tan (bilabial - forelingual)

[wai] - [lai] why - lie (bilabial - forelingual)

[weil] - [jeil] weil - yale (bilabial - mediolingual)

[pik] - [kik] pick - kick (bilabial - backlingual)

[les] - [jes] less - yes (forelingual - mediolingual)

[dei] - [gei] day - gay (forelingual - backlingual)

[sai] - [hai] sigh - high (forelingual - glottal)

[fi:t] - [si:t] feet - seat (labio-dental - forelingual)

Our next point should be made in connection, with another sound property, that is voiced -- voiceless characteristic which depends on the work of the vocal cords. It has long been believed that from the articulatory point of view the distinction between such pairs of consonants as [p, b], [t, d], [k, g], [s, z], [f, v], [?, ?], [?, ?] is based on the absence or presence of vibrations of the vocal cords, or on the absence or presence of voice or tone component. However, there is also energy difference. All voiced consonants are weak (lenis) and all voiceless consonants are strong (fortis).

According to the position of the soft palate consonants can be oral and nasal. There are relatively few consonantal types in English which require the lowered position of the soft palate. They are the nasal occlusive sonorants [m], [n] and [?]. They differ from oral plosives in that the soft palate is lowered allowing the escape of air into the nasal cavity.

It is a well-known fact that no differences of meaning in English can be attributed to the presence or absence of nasalization. It is for this reason that it cannot be a phonologically relevant feature of English consonants, so it is an indispensable concomitant feature of English nasal consonants. Another problem of a phonological character in the English consonantal system is the problem of affricates, that is their phonological status and their number.

The question is: what kind of facts a phonological theory has to explain?

1. Are the English [?, ?] sounds monophonemic entities or biphonemic combinations (sequences, clusters)?

2. If they are monophonemic, how many phonemes of the same kind exist in the system of English consonants, or, in other words, can such clusters as [tr, dr], [?, ?] and [tи, dр] be considered affricates?

Theoretically in each language there might be as many affricates as there are fricatives but in reality the number of them is limited and there are languages where there are none.

According to specialists in English phonetics, there are two affricates in English, they are: [?, ?]. D. Jones points out there are six of them: [?, ?], [ts, ?] and [tr, dr].

A.C. Gimson increases their number adding two more affricates: [tи, dр].

The fact is that Russian phoneticians look at English affricates through the eyes of a phoneme theory, according to which a phoneme has three aspects: articulatory, acoustic and functional, the latter being the most significant one. As to British phoneticians, their primary concern is the articulatory-acoustic unity of these complexes, because their aim is limited by practical reasons of teaching English.

According to N.S. Trubetskoy a sound complex may be considered non-phonemic if:

1. its elements belong to the same syllable;

2. it is produced by one articulatory effort;

3. its duration should not exceed normal duration of either of its elements.

2.3. Modifications of Consonants in Connected Speech

Language in everyday use is not conducted in terms of isolated, separate units; it is performed in connected sequences of larger units, in words, phrases and longer utterances.

Consonants are modified according to the place of articulation.

Assimilation takes place when a sound changes its character in order to become more like a neighbouring sound. The characteristic which can vary in this way is nearly always the place of articulation, and the sounds concerned are commonly those which involve a complete closure at some point in the mouth that is plosives and nasals which may be illustrated as follows:

1. The dental [t], [d], followed by the interdental [и], [р] sounds (partial regressive assimilation when the influence goes backwards from a "latter" sound to an "earlier" one), e.g. "eigth","at the", "breadth", "said that".

2. The post-alveolar [t], [d] under the influence of the post-alveolar [r] (partial regressive assimilation), e.g. "free", "true", "that right word", "dry", "dream", "the third room".

3. The post-alveolar [s], [z] before [?] (complete regressive assimilation), e.g. horse-shoe ['ho:??u:], this shop [рI??'??p], does she [`d???i:].

4. The affricative [t + j], [d + j] combinations (incomplete regressive assimilation), e.g. graduate ['grж?ueit], congratulate [k?n'grж?uleit], did you ['di?u:], could you ['кu?u:], what do you say ['w?t?u:'sei].

The manner of articulation is also changed as a result of assimilation, which includes:

1. Loss of plosion. In the sequence of two plosive consonants the former loses its plosion: glad to see you, great trouble, and old clock (partial regressive assimilations).

2. Nasal plosion. In the sequence of a plosive followed by a nasal sonorant the manner of articulation of the plosive sound and the work of the soft palate are involved, which results in the nasal character of plosion release: sudden, nor now, at night, let me see (partial regressive assimilations).

3. Lateral plosion. In the sequence of a plosive followed by the lateral sonorant [l] the noise production of the plosive stop is changed into that of the lateral stop: settle, table, at last (partial regressive assimilations). It is obvious that in each of the occasions one characteristic feature of the phoneme is lost.

The voicing value of a consonant may also change through assimilation. This type of assimilation affects the work of the vocal cords and the force of articulation. In particular voiced lenis sounds become voiceless fortis when followed by another voiceless sound, e.g.:

1. Fortis voiceless/lenis voiced type of assimilation is best manifested by the regressive assimilation in such words as newspaper (news [z] + paper); goosebeny (goose [s] + berry). In casual informal speech voicing assimilation is often met, e.g. have to do it ['hжf t?'du:], five past two ['faif past 'tu:]. The sounds which assimilate their voicing are usually, as the examples show, voiced lenis fricatives assimilated to the initial voiceless fortis consonant of the following word. Grammatical items, in particular, are most affected: [z] of has, is, does changes to [s], and [v] of of, have becomes [f], e.g.

She's five. Of course.

She has fine eyes. You've spoiled it.

Does Pete like it?

2. The weak forms of the verbs is and has are also assimilated to the final voiceless fortis consonants of the preceding word thus the assimilation is functioning in the progressive direction, e.g.

Your aunt's coming.

What's your name? (partial progressive assimilation)

3. English sonorants [m, n, r, 1, j, w] preceded by the fortis voiceless consonants [p, t, k, s] are partially devoiced, e.g. smart, snake, tray, quick, twins, play, pride (partial progressive assimilation).

Lip position may be affected by the accommodation, the interchange of consonant + vowel type. Labialisation of consonants is traced under the influence of the neighbouring back vowels (accommodation), e.g. pool, moon, rude, soon, who, cool, etc. It is possible to speak about the spread lip position of consonants followed or preceded by front vowels

[i:], [i], e.g. tea - beat; meet - team; feat - leaf, keep - leak; sit - miss (accommodation).

The position of the soft palate is also involved in the accommodation. Slight nasalization as the result of prolonged lowering of the soft palate is sometimes traced in vowels under the influence of the neighbouring sonants [m] and [n], e.g. and, morning, men, come in (accommodation).

Elision or complete loss of sounds, both vowels and consonants, is observed in the structure of English words. It is typical of rapid colloquial speech and marks the following sounds:

1. Loss of [h] in personal and possessive pronouns he, his, her, him and the forms of the auxiliary verb have, has, had is widespread, e.g. What has he done? ['w?t ?z i?d?n].

2. [1] tends to be lost when preceded by [?:], e.g. always ['?:wiz], already [?:'redi], all right [?:'rait].

3. Alveolar plosives are often elided in case the cluster is followed by another consonant, e.g. next day ['neks 'dei], just one [' ??s 'w?n], mashed potatoes ['mж? р?'teit?uz]. If a vowel follows, the consonant remains, e.g. first of all, passed in time. Whole syllables may be elided in rapid speech: library ['laibri], literary ['litri].

Examples of historical elision are also known. They are initial consonants in write, know, knight, the medial consonant [t] in fasten, listen, whistle, castle.

While the elision is a very common process in connected speech, we also occasionally find sounds being inserted. When a word which ends in a vowel is followed by another word beginning with a vowel, the so-called intrusive "r" is sometimes pronounced between the vowels, e.g.

Asia and Africa ['ei ? ?r ?nd 'жfrik?]

the idea of it [рi:ai'di?r ?vit]

ma and pa ['mа:r ?nd 'pa:]

The so-called linking "r," is a common example of insertion, e.g. clearer, a teacher of English.

When the word-final vowel is a diphthong which glides to [i] such as [ai], [ei] the palatal sonorant [j] tends to be inserted, e.g. saying ['seiji?]; trying ['traii?].

In case of the [U]-gliding diphthongs [?u], [au] the bilabial sonorant [w] is sometimes inserted, e.g. going ['g?uwi?], allowing [?'lauwi?].

The process of inserting the sonorants [r], [j] or [w] may seem to contradict the tendency towards the economy of articulatory efforts. The explanation for it lies in the fact that it is apparently easier from the articulatory point of view to insert those sounds than to leave them out.

The insertion of a consonant-like sound, namely a sonorant, interrupts the sequence of two vowels (VV) to make it a more optional syllable type: consonant + vowel (CV). Thus, insertion occurs in connected speech in order to facilitate the process of articulation for the speaker, and not as a way of providing extra information for the listener.

The ability to produce English with an English-like pattern of stress and rhythm involves stress-timing (= the placement of stress only on selected syllables), which in turn requires speakers to take shortcuts in how they pronounce words.

Natural sounding pronunciation in conversational English is achieved through blends, overlapping, reduction and omissions of sounds to accommodate its stresstimed rhythmic pattern, i.e. to squeeze syllables between stressed elements and facilitate their articulation so that the regular timing can be maintained.

Such processes are called coarticulatory/adjustment phenomena and they comprise:

1. change of consonant or vowel quality,

2. loss of consonant or vowels, and even

3. loss of entire syllables :

I must go [m?ssg?u] = vowel change and consonant loss

memory ['memri]= vowel and syllable loss

did you [di??] = consonant blending and vowel change

actually ['жk ? li] = consonant blending, vowel and syllable loss

Syllables or words which are articulated precisely are those high in information content, while those which are weakened, shortened, or dropped are predictable and can be guessed from the context.

2.4. The articulatory classification of English Vowels

The first linguist who tried to describe and classify vowels for all languages was D. Jones. He devised the system of 8 Cardinal Vowels. The basis of the system is physiological. Cardinal vowel No. 1 corresponds to the position of the front part of the tongue raised as closed as possible to the palate. The gradual lowering of the tongue to the back lowest position gives another point for cardinal vowel No.5. The lowest front position of the tongue gives the point for cardinal vowel No.4. The upper back limit for the tongue position gives the point for cardinal No.8. These positions for Cardinal vowels were copied from X-ray photographs. The tongue positions between these points were X-rayed and the equidistant points for No.2, 3, 6, 7 were found. The IPA symbols (International Phonetic Alphabet) for the 8 Cardinal Vowels are: 1 -i, 2 - e, 3 - е, 4 - a, 5 - a:, 6 - , 7 - o, 8 - u.

The system of Cardinal Vowels is an international standard. In spite of the theoretical significance of the Cardinal Vowel system its practical application is limited. In language teaching this system can be learned only by oral instructions from a teacher who knows how to pronounce the Cardinal Vowels.

Russian phoneticians suggest a classification of vowels according to the following principles: 1) stability of articulation; 2) tongue position; 3) lip position; 4) character of the vowel end; 5) length; 6) tenseness.

1. Stability of articulation. This principle is not singled out by British and American phoneticians. Thus, P. Roach writes: "British English (BBC accent) is generally described as having short vowels, long vowels and diphthongs". According to Russian scholars vowels are subdivided into: a) monophthongs (the tongue position is stable); b) diphthongs (it changes, that is the tongue moves from one position to another); c) diphthongoids (an intermediate case, when the change in the position is fairly weak).

Diphthongs are defined differently by different authors. A.C. Gimson, for example, distinguishes 20 vocalic phonemes which are made of vowels and vowel glides. D. Jones defines diphthongs as unisyllabic gliding sounds in the articulation of which the organs of speech start from one position and then elide to another position. There are two vowels in English [i:, u:] that may have a diphthongal glide where they have full length (be, do), and the tendency for diphthongization is becoming gradually stronger.

2. The position of the tongue. According to the horizontal movement
Russian phoneticians distinguish five classes: 1) front; 2) front-retracted; 3)
central; 4) back; 5) back-advanced.

British phoneticians do not single out the classes of front-retracted and back-advanced vowels. So both [i:] and [i] are classed as front, and both [u:] and [Y] are classed as back.

The way British and Russian phoneticians approach the vertical movement of the tongue is also slightly different. British scholars distinguish three classes of vowels: high (or close), mid (or half-open) and low (or open) vowels. Russian phoneticians made the classification more detailed distinguishing two subclasses in each class, i.e. broad and narrow variations of the three vertical positions. Consequently, six groups of vowels are distinguished.

English vowels and diphthongs may be placed on the Cardinal Vowel

3. Another feature of English vowels is lip position. Traditionally three lip positions are distinguished, that is spread, neutral, rounded. Lip rounding takes place rather due to physiological reasons than to any other. Any back vowel in English is produced with rounded lips, the degree of rounding is different and depends on the height of the raised part of the tongue; the higher it is raised the more rounded the lips are.

4.Character of the vowel end. This quality depends on the kind of the articulatory transition from a vowel to a consonant. This transition (VC) is very closed in English unlike Russian. As a result all English short vowels are checked when stressed. The degree of checkness may vary and depends on the following consonants (+ voiceless - voiced - sonorant -).

We should point out that vowel length or quantity has for a long time been the point of disagreement among phoneticians. It is a common knowledge that a vowel like any sound has physical duration. When sounds are used in connected speech they cannot help being influenced by one another. Duration of a vowel depends on the following factors: 1) its own length; 2) the accent of the syllable in which it occurs; 3) phonetic context; 4) the position in a rhythmic structure; 5) the position in a tone group; 6) the position in an utterance; 7) the tempo of the whole utterance; 8) the type of pronunciation. The problem the analysts are concerned with is whether variations in quantity are meaningful (relevant). Such contrasts are investigated in phonology.

5. There is one more articulatory characteristic that needs our attention, namely tenseness. It characterizes the state of the organs of speech at the moment of vowel production. Special instrumental analysis shows that historically long vowels are tense while historically short are lax.



Conclusion

As we could learn from this presentation, speech sounds influence each other in the flow of speech. As a result of the intercourse between consonants and vowels and within each class appear such processes of connected speech.

Despite the importance of speech communication for the entire structure of human society, there are many aspects of the speech communication process that are not fully understood. Research on speech and language is typically carried out by different groups of scientists working on separate aspects of the underlying functional and neural systems. Research from an auditory perspective focuses on the acoustical properties of speech sounds, the representation of speech sounds in the auditory system and how that representation is used to extract phonetic information. Research from psycholinguistic perspectives studies the processes by which representations of meaning are extracted from the acoustic-phonetic sequence, and how these are linked to the construction of higher-level linguistic interpretation in terms of sentences and discourse. However, there has been relatively little interaction between speech researchers from these two groups.

Neither of speech sounds can be separated in the actual process of communication (in the flow of speech). Each of them can be singled out for linguistic analysis. There are some differences between speech sounds - Consonants and Vowels. These differences make it logical to consider each class of sounds independently. All the sounds of a language can be classified in different ways.

Language in everyday use is not conducted in terms of isolated, separate units; it is performed in connected sequences of larger units, in words, phrases and longer utterances. The speech sounds can modify according to the different causes.

In the case of vowels both Russian and British scientists also disagree.

As we can see, the differences between vowels and consonants are more complex than we were probably taught in elementary school. It's less about the letters and more about how our mouth moves when we are saying them.

References

1. Бодуэн де Куртене И.А. Избранные труды по общему языкознанию. - М., 1963.- Т. 1,2.

3. Теоретическая фонетика английского языка: Учебник для студентов институтов и факультетов иностранных языков/ М.А. Соколова, К.П. Гинтовт, И.С. Тихонова, Р.М. Тихонова. - М.: Гуманитарный издательский центр ВЛАДОС, 1996. - 266с.

4. Трубецкой Н.С. Основы фонологии. - М., 1960.

5. Bloch B., Trager G. Outline of Linguistic Analysis. - Baltimore, 1942.

6. Bloomfield L. Language. - N.Y., 1933.