Speech is impossible without the following four mechanisms
1. the power mechanism,
2. the vibrator mechanism,
3. the resonator mechanism,
4. the obstructor mechanism.
The power mechanism consists of the diaphragm, the lungs, the bronchi, the windpipe (or trachea), the glottis, the larynx, the mouth cavity and the nasal cavity.
The vibrator mechanism (the voice producing mechanism) consists of the vocal cords, they are in the larynx. The vocal cords are two elastic folds, they may be opened or closed (completely or incompletely). The opening between them is called the glottis. The pitch of the voice is controlled mostly by the tension of the vocal cords. Voice produced by the vocal cords vibration is modified by the shape and volume of the air passage. When the vocal cords are brought close together and then opened suddenly by the air stream there comes a sort of coughing noise.
This sound is called the glottal stop [ʔ].
The resonator mechanism consists of the pharynx, the larynx, the mouth cavity and the nasal cavity.
The obstructor mechanism consists of the tongue (blade with the tip, front, back or dorsum, rims - the edges of the tongue); the lips; the teeth; the soft palate with the uvula, the hard palate, the alveolar ridge.
It should be borne in mind that the four mechanisms work simultaneously and that each speech sound is the result of the simultaneous work of all of them.
The respiratory, or power mechanism furnishes the flow of air, which is the first requisite for the production of speech sounds. The air stream released by the lungs goes through the windpipe and comes to the larynx. From the larynx the air stream passes to supraglottal cavities that is to the pharynx, the mouth and the nasal cavities. The pharyngeal cavity extends from the top of the larynx to the soft palate, which directs the air stream either to the mouth or nasal cavities which function as the principal resonators. The very end of the soft palate is known as the uvula.
When the soft palate is in its lowered position the air goes up into the nasal cavity, and then out through the nose. When the soft palate is raised the uvula forms a full contact with the back wall of the pharynx and the air stream goes through the mouth cavity. This is the most typical position of the soft palate for most of the sounds of many languages.
The soft palate is the furthest part of the palate from the teeth. Most of the palate is hard. This hard and fixed part of the palate is divided into two sections: the hard palate (the highest part of the palate) and the teeth ridge or alveolar ridge (the part immediately behind the upper front teeth). You can touch the teeth ridge with the tongue-tip.
The lower teeth are not very important for making speech sounds, while the upper teeth take part in the production of many of them. The most important organ of speech is the tongue. The tongue may lie flat or move in the horizontal or vertical directions. It can also change its shape so that the sides are curved up forming a groove.
The tongue consists of several parts:
the part which lies opposite the soft palate is called the back of the tongue; the part facing the hard palate is called the front; the one lying under the teeth ridge is known as the blade and its extremity - the tip.
By the central part of the tongue we mean the area where the back and front meet. The edges of the tongue are known as rims.
The lips can take up various positions as well. They can be brought firmly together or kept apart neutral, rounded, or protruded forward.
All the organs of speech can be divided into two groups: active organs of speech, movable and taking an active part in the sound formation:
the vocal cords which produce voice;
the tongue which is the most flexible, movable organ;
the lips affecting very considerably the shape of the mouth cavity;
the soft palate with the uvula, directing the stream of air either to the mouth or to the nasal cavity:
the back wall of the pharynx contracted for some sounds;
the lower jaw which movement controls the gap between the teeth and also the disposition of the lips;
the lungs providing air for sounds;
passive organs of speech:
the teeth;
the teeth ridge;
the hard palate; «
the walls of the resonators.
There arc three branches of phonetics each corresponding to a different stage in the communicating process mentioned above.
(l)The branch of phonetics that studies the way in, which the air is set in motion, the movements of speech organs and the coordination of these movements in the production of single sounds and trains of sounds is called articulatory phonetics (or physiological).
(la) The branch of phonetics investigating the hearing process is known as auditory (perceptive) phonetics. Its interests lie more in the sensation of hearing, which is brain activity, than in the physiological working of the ear or the nervous activity between the ear and the brain. The means by which we discriminate sounds - quality, sensations of pitch, loudness, length, are relevant here. This branch of phonetics is of great interest to anyone who teaches or studies pronunciation.
(2)Acoustic phonetics studies the way in which the air vibrates between the speaker's mouth and the listener's ear.
(3)The branch of phonetics that studies the linguistic function of consonant and vowel sounds, syllabic structure, word accent and prosodic features, such as pitch, stress and tempo, is called phonology (functional or linguistic phonetics).
Phonetics is itself divided into two major components:
segmental phonetics, which is concerned with individual sounds (i.e. "segments" of speech) and
suprasegmental phonetics whoso domain is the larger units of connected speech: syllables, words, phrases and texts.
Phonetics is connected with linguistic and non-linguistic sciences: acoustics, physiology, psychology, logic, etc.
The connection of phonetics with grammar, lexicology and stylistics is exercised first of all via orthography, which in its turn is very closely connected with phonetics. Phonetics formulates the rules of pronunciation for separate sounds and sound combinations.
Through the system of rules of reading phonetics is connected with grammar and helps to pronounce correctly singular and plural forms of nouns, the past tense forms and past participles of English regular verbs. E.g.
[d] is pronounced after voiced consonants (beg - begged)
[t] is pronounced after voiceless consonants (wish - wished)
[ɪd] is pronounced after [t] (want - wanted)
[s] is pronounced after voiceless consonants (books)
[z] is pronounced after voiced consonants (bags)
[ɪz] is pronounced after sibilants (boxes)
One of the most important phonetic phenomena - sound interchange - is another example of the connection of phonetics with grammar. For instance, this connection can be observed in the category of number. Thus, the interchange of [f-v], [s-z] helps to differentiate singular and plural forms of such nouns as calf-calves, leaf-leaves, house-houses.
Vowel interchange is connected with the tense forms of irregular verbs, eg: sing-sang-sung, write-wrote-written.
Vowel interchange can also help to distinguish between:
nouns and verbs bath-bathe
adjectives and nouns hot-heat
verbs and adjectives moderate-moderate
nouns and nouns shade-shadow
nouns and adjectives type-typical
Phonetics is also connected with grammar through its intonation component. Sometimes intonation alone can serve to single out the logical predicate of the sentence. Compare:
He came out. (Not Mary or John)
He came home. (So you can see him now)
He came home. (He is at home, and you said he was going to the club)
In affirmative sentences the rising nuclear tone may serve to show that it is a question.
Phonetics is also connected with lexicology. It is only due to the presence of stress, or accent, in the right place, that we can distinguish certain nouns from verbs (formed by conversion). E.g.:
ˈabstract - to ab ' stract ˈobject - to ob ' ject ' transfer - to trans ' fer
Homographs can be differentiated only due to pronunciation, because they are identical in spelling, eg: bow (лук - поклон), lead (руководство - свинец), row (ряд - шум), sewer (швея - сточная труба), tear (разрыв - слеза), wind (ветер - виток)
Due to the position of word accent we can distinguish between homonymous words and word groups, e.g. 'blackbird дрозд - 'black 'bird - черная птица
Phonetics is also connected with stylistics; first of all through intonation and its components: speech melody, utterance stress, rhythm, pausation and voice timbre which serve to express emotions, to distinguish between different attitudes on the part of the author and speaker. Very often the writer helps the reader to interpret his ideas through special words and remarks such as: a pause, a short pause, angrily, hopefully, gently, incredulously, etc.
E.g.
"Now let me ask you girls and boys, would you paper a room with representations of horses?"
After a pause, one half of the children cried in chorus. "Yes. sir!" Upon which the other half, seeing in the gentleman's face that "Yes" was wrong, cried out in chorus. "No. sir!" - as the custom is in these examinations.
"Of course, no. Why wouldn't you?"
A pause. (Ch. Dickens. Hard Times)
Phonetics is also connected with stylistics through repetition of words, phrases and sounds. Repetition of this kind serves the basis of rhythm, thyme alliteration.
Regular recurrence of accented elements, or rhythm, may be used as a special device not only in poetry, but in prose as well.
For example, in the extract given below the repetition of the word fact helps Ch. Dickens to characterize his hero, Mr. Gradgrind as a narrow-minded person unable to see anything behind bare facts.
"Now, what I want is Facts, leach these boys and girls nothing but Facts. Facts alone are wanted in life. Plant nothing else and root out everything else. You can only form the minds of reasoning animals upon Facts: nothing else will ever be of any service to them."
The repetition of identical or similar sounds, which is called alliteration, helps, together with the words to which they belong, to impart a melodic effect to the utterance and to express certain emotions. Thus, the repetition of the sonant [m] in the lines of the ballad, given below (together with the other stylistic devices), helps to produce the effect of merriment.
There arc twelve months in all the year, as 1 hear many men say. But the merriest month in all the year is the merry month of May.
The repetition of the words year, say and May produces the effect of rhyme.