COAL CITY UNIVERSITY

FACULTY OF ARTS AND SOCIAL SCIENCES

DEPARTMENT OF ENGLISH AND LITERARY STUDIES

COURSE CODE: ELS 123

COURSE TITLE: INTRODUCTION TO PHONETICS

COURSE LECTURER: BASSEY, MARY DOMINIC

COURSE DESCRIPTION/AIM

The elementary aspects of phonetics and mechanics of sound production are introduced in this course. There is emphasis on the organs of speech and their functions in speech production; basic segmental features of English and their contrasting patterns, together with the use of minimal pairs. The aim is to improve the intelligibility of the students spoken English.

COURSE CONTENT/ COURSE OUTLINE

Definition of Phonetics

Branches of phonetics

Organs of speech and their functions

Airstream mechanism

Phonation types

Description and classification of segments (consonants and vowels)according to IPA (International Phonetic Alphabet)

Articulation types

Prosodic features/ Suprasegmental features

PHONETICS

Phonetics is the study of human speech sounds. It studies the actual sounds that the human vocal organs are capable of producing. It identifies, classifies and describes human speech sounds. There are three branches of phonetics namely; articulatory phonetics, acoustics and auditory phonetics.

Articulatory Phonetics: This branch of phonetics studies the human vocal organs and how speech sounds are produced using these organs. There are three phases of articulatory phonetics namely; the initiation phase, the phonatory phase and the articulatory phase.

The Initiation Phase: This has to do with the source of the air that is responsible for the production of a particular sound. The air for each sound could be initiated from the lungs, the pharynx or the velum.

The Phonatory Phase: This has to do with voicing. It deals with the state of the glottis that is whether the sounds produced are voiced or voiceless sounds.

The Articulatory Phase: This has to do with the different articulators that are responsible for speech sounds. It is concerned with how the speech organs come together to produce speech sounds.

Acoustics Phonetics:This is a branch of phonetics that studies the physical transmission of speech sounds. It deals with sound waves and how sounds travel from the speaker to the hearer.

Auditory Phonetics:This is the branch of phonetics that is concerned with speech perception. It studies how speech sounds are being perceived by the hearers.

ORGANS OF SPEECH

Organs of speech are those parts of the body that interact in the production of speech sounds. They were not designed specifically for speech; they have their primary biological function. Therefore speech adaptation is only a secondary function of these organs. These organs are broadly classified into three namely; the respiratory system, the phonatory system and the articulatory system.

The Respiratory System: The respiratory system comprises of the lungs, the diaphragm, the trachea (windpipe) and the bronchial tubes. The lungs are large spongy bodies consisting of many tubes in a descending order of size within a cavity formed by the rib cage and the diaphragm. It is like an inverted tree which branches first into two large tubes called the bronchial tubes at the base of the wind pipe and then into smaller tubes known as bronchioles and then into much smaller tubes known as the alveoli. The lungs are the basis of the respiratory system and perform the primary biological function of supplying the blood with oxygen and cleansing it of carbon-dioxide. The diaphragm is the muscle that separates the stomach from the thoraxic cavity. The

thoraxic cavity is the region in the mammalian body between the neck and abdomen as well as the cavity containing the heart and lungs. The two lungs are joined with two tubes known as the bronchial tubes. The moment they join together and become one, they become the trachea (windpipe).

The Phonatory System:The phonatory system comprises of the larynx and the pharynx. The larynx is a casing made up of muscles and cartilages. It is situated in the upper part of the windpipe (trachea). The forward part of the larynx is prominent in the neck below the chin and quite noticeable in adult males, and is commonly called the Adam’s apple. The larynx is the voice box. It houses the vocal cords. The vocal cords/folds are made up of ligaments and elastic tissues which appear as thin lips stretching across the larynx. The vocal cords can be brought together or separated by the movement of the cartilages. Hence, the vocal cord can either be open in a v-shape form or closed along their entire length. The opening between the vocal cords is known as the glottis. The main function of the vocal folds is to produce voice, to make speech audible. Biologically the primary function of the vocal cords is to act as a valve which can prevent foreign bodies into the trachea and lungs or which may have the effect of enclosing the hair within the lungs to assist in muscular effort on the part of the arms or abdomen. Above the glottis, we have the pharyngeal, the nasal and the oral cavities which are otherwise referred to as the supra glottal cavities. These cavities function in speech as resonators of the tone or sound produced by the larynx.

The pharynx is the cavity or chamber above the larynx, behind the mouth and nose. There are three parts of the pharynx namely; the laryngopharynx which is the part of the pharynx immediately above the larynx, the oro-pharynx which is the part of the pharynx leading towards the oral cavity and the naso-pharynx which is the part of the phaynx leading towards the nasal cavity.

The Articulatory System: The articulatory system comprises of the mouth (oral cavity) and the articulators. The organs in the oral cavity are divided into two namely; organs at the roof of the mouth (upper part) and organs at the floor of the mouth (lower part). The organs at the roof of the mouth include the upper lip, upper teeth, the alveolar ridge (upper teeth ridge), hard palate, soft palate (velum) and the uvular. The alveolar ridge is like a bridge and is clearly seen behind the teeth. The hard palate is a bony arch-like structure after the teeth ridge while the soft palate also known as the velum which can be raised or lowered and the curve of the hard palate is what gives way to the velum. The uvular is the extension of the velum that is hanging down at the roof of the mouth. The velum terminates at the extreme of the roof of the mouth with as little hanging point known as the uvular. The organs at the floor of the mouth include the lower lip, the lower teeth and the tongue. The tongue is divided into the tip/apex, the front, the blade the centre, back and root. The tip of the tongue is the extreme front position of the tongue. The blade is the part that follows immediately after the tip, in other words, the side of the tongue. The front is the part of the tongue lying opposite the hard palate in its resting position. The back is the part of the tongue that lies opposite the soft palate when it stretches. The root is the part of the tongue that lies

adjacent to the pharyngeal wall. The root could be pushed forward of which it widens the pharyngeal wall, hence we have an advanced tongue root [ATR] but if it is pulled backwards it narrows the pharyngeal wall, hence we have a retracted tongue root. The articulators are those organs that are above the larynx. They are divided into two; the active and the passive articulators. The passive articulators are those articulators at the roof of the mouth while the passive articulators are the articulators at the floor of the mouth. The passive articulators remain where they are while the active articulators initiate the movement by going to meet the passive articulators where they are to make contact, hence the name active articulators. The teeth, the hard palate and the pharyngeal wall are the only parts of the oral chamber that are relatively fixed while others are moveable. The lips is the only moveable part that affects considerably the shape of the oral cavity, they vary in rounding and protrusion to extreme spread. Hence, they can be said to be rounded or unrounded in the production of sounds.

AIRSTREAM MECHANISM

An airstream is a moving current of air brought about by the movement of the organs of speech. It is made possible by the action of certain parts of the organs attached to the wall of a chamber which is made flexible and with the ability of being enlarged or reduced in volume. This part of the organ which is capable of enlarging or reducing the air chamber is known as the initiators. Air can be pulled in or pushed out through the help of the initiator. The action or movement of the initiator initiates the airstream which provides the sound energy. The air chamber is where the air for each airstream is enclosed. An initiator together with its air chamber constitutes an airstream mechanism. The direction of the airstream can be egressive or ingressive. When the body of air in the chamber of a particular airstream mechanism is pushed out by the movements of the initiator from the centre of the chamber, we have an egressive airstream but when the body of air is pulled in by an outward movement of the initiator away from the centre of the chamber, we have an ingressive airstream. Air is rarefied in the ingressive airstream while in the egressive airstream, air is compressed.

There are three types of airstream mechanism namely;

a. The pulmonic airstream mechanismb. The glottalic airstream mechanismc. The velaric airstream mechanism

Pulmonic Airstream Mechanism: The lungs constitute the air chamber for the pulmonic airstream mechanism while the respiratory muscles (muscles surrounding the lungs/the rib cage) with or without the diaphragm make up the initiator. When the walls of the lungs are moved up, air is expelled from the lungs and we have a pulmonic egressive airstream but when the walls of the lungs are moved downwards and air is taken in, we have the pulmonic ingressive airstream. All sounds in English language and majority of the sounds in other languages of the world are

produced using the pulmonic egressive airstream mechanism while the pulmonic ingressive is used for paralinguistics acts such as voice disguise and non-linguistics acts such as voice disguise and yawning, snoring e t c.

Glottalic Airstream Mechanism: The air above the closed glottis in the pharyngeal cavity constitutes the body of air that is set in motion in this airstream. The pharyngeal cavity is the air chamber while the closed glottis is the initiator. The closed glottis can be moved up and down. When air is forced out by an upward movement of the closed, we have the glottalic egressive airstream and when air is sucked in by its downward movement, we have a glottalic ingressive airstream. Sounds produced with the glottallicegressive airstream are known as ejectives. Ejectives are often unvoiced and represented with the symbol [’] after a consonant or cluster of consonants like [p’ t’ k’]. They are found in Hausa and Zulu languages while sounds produced with the glottalic ingressive airstream are known as implosives which are either voiced or unvoiced. They are transcribed with a right-faced hook attached to the consonant symbol for plosives like [ƥ ɓ ɗ]. Ejectives can be fricatives or stops while implosives are always stops.

Velaric Airstream Mechanism: This is also known as the oral airstream mechanism because the oral cavity constitutes the air chamber for it. The initiator is the firm contact made between the back of the tongue and the velum. When the back of the tongue in contact with the velum is pushed forward in the mouth, we have the velaricegressive airstream and when it is pulled downwards and backwards sucking air into the mouth, we have the velaric ingressive airstream. Clicks are sounds produced with the velaric ingressive airstream. They are found in South African and South Western African languages – Xhosa, Zulu, Khoisa.clicks can be voiced or voiceless. They are voiced when a pulmonic airstream is used simultaneously. No language is said to employ the velaricegressive airstream in the production of speech sounds. Examples of clicks include the bilabial, dental, alveolar, palate-alveolar and alveolar lateral respectively [ʘ ǀ ǃ ǂ ǁ].

Clicks, implosives and ejectives are non- pulmonic sounds. They are not produced with the source of air from the lungs.

PHONATION TYPES

Phonation refers to the act of sound-making. The term phonatory is used to refer to the states which the glottis assumes in the production of sounds. The states of the glottis include the following:

The Voiceless State of the Glottis: Here, the vocal cords are drawn wide apart so that the airstream passes through the opening quite freely. This is the state the glottis assumes during quiet and normal breathing. When the glottis assumes this state for the production of a speech sound, it is open and said to be in a state of breath. Sounds produced with this state of the glottis are known as voiceless sounds and are produced with breath.

Voiced state of the glottis: This state of the glottis is also known as the glottis in vibration. Here, the vocal cords are drawn loosely together in such a way that they are set into vibration as the airstream from the lungs passes through them. All languages of the world employ this state of the glottis.

Breathy voice state of the glottis: This state of the glottis is characterized by some vibration of the vocal cords as well as a free flow of air at the same time through the glottis. The glottis is fairly open at one end and narrower at the other end. They are not as close in voiced state neither are they open as in voiceless state but there is a little opening which causes the vocal cords to flap as air passes through them with force. Sounds produced with the glottis in this state are known as murmured or breathy-voiced. It is marked by the use of a subscript umlaut [..] under the symbol for a voiced segment.

Whisper state of the glottis: This is also known as the narrow state of the glottis. Here, the vocal cords are so narrowed that the airstream is disturbed as it passes through them with a soft hissing noise that is technically known as whisper. The vocal cords are not so close to be set in vibration and are not as wide apart as in the open state. Sounds produced with this state of the glottis are known as whispered.

Creaky voice state of the glottis: This is also known as the laryngealised state of the glottis. Here, the anterior ligamental ends of the glottis are brought together in such a way that they are set in vibration by the force of the passing airstream while the arytenoid cartilage at the posterior end is held tightly together. The noise that is emitted in this state is referred to as glottal fry. This is the state the glottis assumes when in lifting an heavy object, one tries to prevent air from slipping away which could affect the muscular effort. A tilde is usually placed under the symbol for a voiceless sound to indicate a creaky voice.

Closed glottis: Here, the glottis is completely closed as the vocal cords are brought tightly together with such firmness that the airstream cannot force them apart. The only sound that is produced with this state of the glottis is the glottal stop and is symbolized as [?]. The glottal stop is found in Hausa, Fulfulde languages. This is the state of the glottis that is used for non-linguistic acts such as coughs and hiccups.

DESCRIPTION AND CLASSIFICATION OF SOUNDS

The sounds that we make in speech are of two types and they are the vowel sounds and the consonant sounds. They are also known as segments.

CONSONANTS

Consonants are sounds produced with the obstruction of the flow of air while vowel sounds are made without such obstruction. There are three main criteria for describing or classifying consonants according to IPA (International Phonetic Alphabet) and they are; state of the glottis, place of articulation and manner of articulation. The state of the glottis refers to the state the glottis assumes in the production of a consonant sound. The state of the glottis may be voiced or voiceless in the production of a consonant sound, hence the sounds are either voiced e g [v] or voiceless [f]. The place of articulation is the point where the air for speech production is obstructed; this could involve contact between the two lips (Bilabial), the lower lip and the upper front teeth (Labiodental), the tip/blade of the tongue with the back of the upper teeth/alveolar ridge (Dental), tip/blade of the tongue and the alveolar ridge (Alveolar), tip/blade of the tongue and the region between the alveolar ridge and the hard palate (Palatal alveolar/post alveolar/alveopalatal), the tip of the tongue curled backwards to the hard palate (Retroflex), the front of the tongue and the hard palate (Palatal), the back of the tongue and the soft palate/velum (Velar), the back of the tongue and the uvular (Uvular), the root of the tongue and the pharyngeal wall (Pharyngeal), the two vocal cords (Glottal). The following are examples of sounds that belong to the aforementioned places of articulation respectively [p v ɵ t ʃɽɲ ŋ ʁ ʕ Ɂ]. Manner of articulation describes the way the airstream is interrupted by the various organs of speech. It is technically referred to as stricture, that is, the degree of the closure of the vocal tract. There are three ways by which the vocal tract could be obstructed; by a complete obstruction of the air passage, by narrowing the air passage so that audible friction is heard and by slightly narrowing the air passage without causing any audible friction that the air flows out freely. Sounds produced by a complete obstruction of the flow of air are known as stops. Stops can be classified based on the vellic action and the type of airstream mechanism involved. Oral and nasal stops are stops produced based on the vellic action. The velum may be lowered thereby blocking the part that leads to the vocal tract and allowing air to pass through the nostrils; hence, a nasal stop is produced. The velum may also be raised thereby blocking the tract that leads to the nasal cavity and allowing air to flow out through the mouth; hence, an oral stop is produced. The oral stop is further sub-classified into plosives, ejectives, implosives and clicks based on the type of airstream mechanism involved which are pulmonic egressive airstream mechanism, glottalic egressive airstream mechanism, glottalic ingressive airstream mechanism and velaric ingressive airstream mechanism respectively. Sounds produced by the narrowing of the air passage so that audible friction is heard include; fricatives and affricates. Fricatives are sounds produced by a partial obstruction of the airstream so that audible friction is heard as the air passes through the narrow closure of the vocal tract. They may be classified into flat and grooved fricatives based on the amount of friction noise that accompanies their production. Flat also known as slit fricatives are

produce with the tongue flat in the mouth with a wide slit as the air passes out with some turbulence [f v ɵð]. The grooved fricatives are produced with great friction noise with the tongue forming a groove directed over the teeth [s z]. Fricatives can also be classified into central and lateral based on the direction of the friction noise. Central fricatives are fricatives in which the friction noise flows out centrally, all fricatives are classified as central apart from the lateral fricatives while lateral fricatives are fricatives in which the friction noise flows out from the sides of the mouth, they are found in Zulu [ɬ ɮ]. Affricates are sounds produced by the combination of a plosive and fricative stricture in a sequence but as a unit [ʧ ʤ]. Approximant is a sound produced by slightly narrowing the air passage without causing any noticeable noise or friction. They are also known as frictionless continuants, semi- vowels or glides. Approximants can be classified into central and lateral approximant. Central approximants are produced with the air flowing out centrally without any friction [w j] while lateral approximants are produced with the air escaping from the sides of the mouth [L]. Hence, the description of the consonant [p] would be voiceless bilabial plosive e t c.

Other consonantal gestures

In addition to stops, fricatives and approximants, there are other consonantal gestures which include; tap, flap and trill/roll. Taps are produced by the obstruction of the airstream by one hit or single tap of the active articulator against the passive one [ɾ]. Flap though sometimes regarded as tap involves the active articulator striking against the passive one in passing as it returns to its rest position [ɽ]. Trill also known as roll is produced when the active articulator vibrates against the passive one thereby shutting off and releasing the flow of air in brief periods, they may involve series of two or three taps [r].

Fig 1: The IPA Consonant Chart

ENGLISH CONSONANTS

There are twenty-four consonants in English

Bilabial Labio-dental

Dental Alveolar Palato-alveolar

Palatal Velar Glottal

Plosive P b t d k gFricative f v ɵð s z ʃ ӡ HAffricate ʧ ʤNasal m n ŋ Lateral approximant

l

Trill/liquid rSemi-vowel w j

Fig 2: English Consonant Chart

VOWELS

Vowels are sounds produced with a spontaneous flow of air. They can be defined as central, resonant, continuant oral sounds. Vowels are regarded as central because the air flows out from the centre of the mouth; they are resonant because there is no friction in the production of the sounds while they are continuant because there is no obstruction of the airstream as they flow continually until they have been completed. They are regarded as oral sounds because the air flows out through the mouth except there is a modification influenced by their environment of occurrence. There are three main criteria for describing and classifying vowels according to IPA (International Phonetic Alphabet) and they are; height of the tongue, part of the tongue raised and shape of the lips. The height of the tongue is the highest position of the tongue (hump) with respect to the root in the production of a particular vowel. The tongue could be as high as possible to the roof of the mouth when producing a particular vowel and such vowels are known as close vowels/high vowels [i] and the tongue could be as low as possible to the floor of the mouth when producing a particular vowel and such vowels are known as open vowel/low vowel [ɑ]. The intermediate positions between these two vowels are known as close-mid/half-close and open-mid/half – open respectively. The part of the tongue that could be raised in the production of a vowel could be either the front for front vowels [i], the centre for central vowels [Ʌ] or the back for back vowels [u]. The shape of the lips could be rounded for rounded vowels [o] or spread for unrounded vowel [e] in the production of a vowel. Hence, the description of the vowel [i] would be close front unrounded vowel e t c

The Primary Cardinal Vowel

The primary cardinal vowels are vowels used as a reference vowel for describing vowels of other languages. It is an arbitrary independent vowel system devised by Daniel Jones.They do not belong to any vowel of any particular language and act as boundary limits in vowel sound production because they are produced at extreme positions in the mouth or limit of the total vowel area,Yul- Ifode (2008). Cardinal vowels are also known as peripheral vowels. There are eight primary cardinal vowels; five of them are unrounded while three are rounded. The primary cardinal vowel 1 [i] and 5 [ɑ] are referred to as hinge vowels.

Front Centre Back

Close i u

Close-mid e o

Open-mid ɛ ɔ

Open a ɑ

Fig 3: The Primary Cardinal Vowel Chart

The secondary cardinal vowel and other vowel positions

There are eight secondary cardinal vowels; five of them are rounded while three are unrounded. They are not all peripheral as the primary cardinal vowels but they have fixed and unchanging quality like the primary cardinal vowels. The secondary cardinal vowel 9 to 13 are rounded while 14 to 16 are unrounded unlike in the primary cardinal vowel where 1 to 5 are unrounded while 6 to 8 are unrounded. The other vowel positions are mainly central vowels.

Fig 4: The Primary and the Secondary Cardinal Vowel Chart with other vowel positions (IPA chart).

VOWELS OF ENGLISH

There are twenty-five vowels in English and they are divided into three namely; monophthongs, diphthongs and triphthongs.

Monophthongs:These are vowels that do not involve any noticeable change in quality in their production. They are also known as pure vowels. There are twelve monophthongs in English and they are divided into long and short. The long ones are produced with longer vowel duration than the short ones and are usually indicated with a colon before the long vowel.The following are monophthongs in English;

/i:/ as in peak

/ı/ as in pick

/ɛ/ as in bed

/ӕ/ as in bad

/a:/ as in laugh

/ɔ/ as in yacht

/ɔ:/ as in port

/ᶷ/ as in sugar

/ᶷ:/ as in food

/Ʌ/ as in love

/ə:/ as in bird

/ə/ as in father

Diphthongs: These are vowels that involve a change from one vowel quality to the other.There are eight diphthongs in English and they are divided into closing and the centering diphthongs. The closing diphthongs are produced when there is a movement from an opening vowel position to a closed vowel position while the centering diphthongs are produced when the tongue glides towards the centre of the tongue as in the case of the central vowel, schwa [ə] which must always accompany all centering diphthong. The following are diphthongs in English;

/ei/ as in baby

/əu/ as in note

/ai/ as in eye

/au/ as in doubt

/ɔi/ as in boy

/iə/ as in fear

/eə/ as in heir

/uə/ as in cure

Triphthongs: These are vowels that involve two detectable changes in quality. It is the combination of three vowel sounds which are pronounced as a unit. There are five triphthongs in English;

/eiə / as in player

/aiə/ as in fire

/ɔiə/ as in loyal

/əuə/ as in lower

/auə/ as in tower

ARTICULATION TYPES

There are two broad types of articulation based on the type of strictures involved and they are; simple/single and complex articulation.

Simple/single articulation: This is a type of articulation which involves only one primary stricture in one place of articulation e g [p]

Complex articulation: This is a type of articulation which involves one stricture at two different places of articulation or two different strictures at the same place of articulation. There are three types of complex articulation and they are; sequential, double and secondary articulation.

Sequential articulation: This is when sounds are produced with two primary single strictures occurring as a sequence, one stricture after the other and often in one place of articulation e g affricates. An affricate is made up of the combination of a plosive and fricative stricture in a sequence e g [ʧ] and [ʤ].

Double articulation: This involves the combination of two single strictures of the same type in two different places of articulation both occurring at the same time and not a movement from one

stricture to the another as with affricates. The articulators here are of equal strength, non is subordinate to the other e g labial velars [kp] and [gb] as in [kpe] ‘call’ and [gbe] ‘carry’ in Yoruba.

Secondary articulation: This involves the superimposition of an articulation with a lesser degree of stricture on another one with a greater degree of stricture. The primary stricture is the one with the greater degree of closure while the secondary stricture is that with less a stricture. There are several types of secondary strictures and they are as follows;

Labialization: This is a secondary articulation that involves the addition of lip rounding to a primary stricture in the production in the production of particular segments. It is symbolized by a raised [w]after the segment with the primary stricture.

Palatization: This involves the addition of a high front tongue position like the vowel [i] to the main articulation of a consonant sound. It is symbolized by a raised [j] after the segment with the primary stricture.

Velarization: This is the superimposition of a secondary stricture which involves the raising of the back of the tongue to the same position as it occupies in the production of a close back unrounded vowel [ɯ]in the production of a segment. It often occurs with the production of the English dark/velarised L [ƚ].

Pharyngealisation: This involves the addition of a back unrounded vowel-like tongue positionas for [ҁ] to a primary stricture. It is symbolized by the use tilde just like in velarization.

Glottalisation: This involves the superimposition of a glottal constriction as in the glottal stop on a primary stricture. It is symbolized with a raised glottal stop sign [Ɂ] or an apostrophe [’] placed after the symbol with the primary stricture.

Nasalization: This involves an addition of a nasal feature to a primary stricture without inherent nasality. It is phonetically considered as a modification that involves the superimposition of a lowered velum (nasal resonance) on an oral sound. It is often found in vowels when they occur in the environment of nasal consonants.

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SUPRASEGMENTAL FEATURES

Suprasegmental features are those features that spread over more than one segment of speech. They are also known as prosodic features or prosodies. These features are marked over segments or superimposed on segments; hence they are seen as beyond the segments. They include; the syllable, pitch, stress, tone and intonation.

SYLLABLE: There are several theories that describe the syllable. Yul-Ifode (2008), identifies two of these theories namely; the stetson’s motor chest theory and the prominence theory. The stetson’s motor chest theory identifies a correlation between the syllable and bursts of activity of the intercostals muscles. Each syllable is said to correspond to an increase in air pressure released from the lungs in a series of chest pulses, the increase being greater in emphatic speech. Syllables are thus emitted one at a time by the speaker as independent muscular gestures. The criticism inherent in this theory is that it is difficult to measure chest pulses, particularly when two vowels co-occur as a sequence of two syllables but said in a singular muscular effort e g buying [baiŋ], sewing [səuŋ]. The prominence theory argues that in any given string of sounds some sounds are intrinsically more sonorous than the others, the central part of the syllable being identified at each peak of sonority and vowels with greater power constitute such peaks of sonority or prominence while consonants are considered less sonorous and are usually found at the valleys of prominence e g bag [bӕg] and go [gəu]. The criticism inherent in this theory is that it has failed in identifying clear boundaries in certain adjacent syllables. Although one can put a boundary in go and bag but one cannot put a boundary in words like danger and buster. There is no universal acceptable definition of syllables; most definitions seem to allow in the principle of location of peaks but fail to tell where to place boundaries between syllables. However, a syllable may be defined as sequences of sounds which can be pronounced in isolation. Consonants and vowels are the constituents of the syllable. Every syllable must have a nucleus. The nucleus is usually a vowel but when there is no vowel, it can be a syllabic nasal or liquid. The nucleus is marked with a vertical stroke under the sound if it is a consonant [!] e g []. The nucleus can be the only member of a syllable e g [] oh. A syllable in addition to the nucleus may begin or end with a consonant. When the nucleus is not followed by any consonant at the end, the syllable is called an open syllable and the syllable structure will be cv, ccv, cccv e t c. when the nucleus is followed by a consonant, the syllable is called a closed syllable. The consonant constituting the opening segment is the onset while the consonant constituting the closing segment is the coda. The nucleus either a vowel, syllabic nasal or liquid is known as the centre or peak. The onset and the coda are collectively known as margins while the nucleus and the coda are collectively known as rhyme.

PITCH: This is the auditory phonetic attribute of a sound, the situation which enables a speaker and a listener to order and place the sound on a scale going from high to low and vice versa. It is directly related to the rate of the vocal cords. One of the factors that determine pitch of a sound is the tension of the vocal cords, the rate of air flow from the lungs, different states of the glottis. There is rise in pitch in the whisper state of the glottis and low pitch in the creaky state of the glottis. The pitch of the voice can be used to convey information such as stress, tone and intonation. The variation of the pitch of the voice can be used to indicate certain personal characteristics of an individual whether one is a male or female, adult or child e t c or the emotional state of an individual. Change of pitch is achieved by stretching and tensing the vocal cords and changing the sub-glottal pressure.

STRESS: This is the degree of force employed in the production of a syllable. There are two distinctions of stress namely; stressed and unstressed. A sound is stressed if during its production relatively greater articulatory energy is expended on it. A change in stress means a change in the degree of force or initiatory power. The basis for the manifestation of stress is the pulmonic pressure. Stress is marked in the IPA with the use of a short raised vertical line. Engglish is a stressed language. There are three degrees of stress in English namely; primary, secondary and unstressed. The primary stress is the stress which carries the greater force and is marked by a superscript while the secondary stress is the stress that is produced with a lesser force and is marked by a subscript, the unstressed is produced without any degree of stress and is marked without any sign. Monosyllabic words are not stressed in English because a single syllable does not constitute peak in articulatory force. Every content word in English is stressed. Stress can sometimes be achieved by lengthening a syllable or vowel. A syllable with the primary stress in English usually sounds longer. Stress is significant in differentiating the meaning of words as in import(n) and im port(v).

TONES: This refers to variations in pitch which affects the meaning of words. It is a function of pitch in distinguishing the meanings of words and is usually marked on syllabic segments of a language. Tones are enclosed in square brackets before segments or marked above segments orthographical. Tones languages are languages whose words are made up of vowels and consonants as well as tones and the tones bring about changes in the meaning of words. Many African and Asian languages are tone languages. There are two types of tones and they are; level tones and contour tones. Level tones are tones that remain at one unchanging pitch level. Languages that mainly use level tones are known as level tones or register tone languages. There are three types of level tones; low, mid and high. An example of a language with the three level tones is Yoruba. Register tone languages have other features of tones known as downstep while others use downdrift. Downstep is the non-authomatic non-predictable lowering of tones as in the sequence of two high tones in a word in Ibibio where the second tone is higher than the first..Downdrift is a phenomenon that involves the authomatic lowering of a high tone by a preceding non-initial low or of a low tone by a preceeding high which is already lowered. Languages with downdrift are known as terraced level language while those without are called

descrete level languages. Both downdrift and downstep are found in terraced level languages and they are collectively known as register lowering or key lowering. Contour tone is also known as gliding tones. Languages that have tones that are rising and falling are known as contour tone language

INTONATION: This refers to pitch patterns which stress over whole phrases and sentences. It is therefore the pitch variation, the overall pitch contour of a sentence. The variation changes in the pitch of the voice in the same utterance give rise to different intonation patterns distinguished for a particular language. Intonation can perform the following functions; attitudinal and syntagmatic function. Attitudinal function is used to express emotions such as anger, sadness, indecision, happiness e t c. The syntagmatic function is divided into accentual, grammatical or discourse. Accentual helps to produce prominence on syllable that needs to be perceived as stressed syllables and in particular placing of tonic stress. It marks out the words to which it belongs as the most important units and also indicates the place of a speaker. Grammatical function is when it aids the listener in recognizing the grammatical or the syntactic structure of the utterance that is being said through the information provided by intonation. In English a falling pitch movement is associated with statements while a rising pitch turns into a yes or no question. Discourse can be used to signal a listener what could be taken as new information and what is already given. It can suggest when a speaker is indicating some sort of contrast or link with material in another tone unit. In conversation, it can convey to the listener what kind of response is expected. Discourse can also be used to show how clauses and sentences go together in spoken discourse for example subordinate clauses often have lower pitches, faster tempo and narrower pitch range than their main clause.

QUESTIONS FOR DISCUSSION

1. What is phonetics?2. There are two types of sounds in speech production, discuss the criteria for describing

these sounds.

REFERENCES

Ladefoged, P. 1985. A Course in Phonetics. 2nd Edition. New York: Harcourt Brace Jovansovich.Yul-Ifode, Shirley. 2008. Basic Phonetics. Port Harcourt: University of Port Harcourt

RECOMMENDED TEXT

A Course in Phonetics 6th edition by Peter Ladefoged and Keith JohnsonCambridge English Pronouncing Dictionary by Daniel Jones.