Andrew Radford - Linguistics An Introduction [Second Edition]

For these reasons, linguists have developed systems of phonetic transcription in which each sound is represented by just one symbol and each symbol represents just one sound. Unfortunately, there are several such systems in use. In this book, we will use the transcription system of the International Phonetics Association, which is generally referred to as the IPA. This system, commonly used in Britain, derives from one developed in the 1920s by Daniel Jones and his colleagues at London University, one of whose aims was to provide writing systems for the

unwritten languages of Africa and elsewhere.

One advantage of the IPA is that it is accompanied by a well-defined method of describing sounds in terms of the way in which they are produced. An understanding 27

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sounds

Figure 4 Cross-section of the human vocal tract

of how speech sounds are produced is a prerequisite for being able to transcribe them, so our introduction of the various symbols employed in the IPA will be accompanied by an account of the mechanisms of speech production.

Any sound is a series of vibrations moving through air, water or some other

material. To create these vibrations, a sound source is needed and these come in various types. On a guitar, for instance, the sound source is the strings, which vibrate when plucked. By themselves, these produce relatively little noise, but the body of the instrument is basically a wooden box which amplifies the sounds by picking up their vibrations and resonating, that is, vibrating in the same way, but more loudly. If you strum more than one string on a guitar, the pattern of resonance becomes very complex, with several sets of vibrations resonating at once. Speech sounds are produced in basically the same way, with bands of tissue called the vocal cords or vocal folds corresponding to the guitar strings. These are situated in the larynx or voice box, a structure in the throat (see figure 4). When air is forced out of the lungs, it causes the vocal cords to vibrate. Corresponding to the body of a guitar and functioning as a resonating chamber is the mouth and nose cavity above the larynx. Taken together, all these structures are called the vocal tract. The major difference between a guitar and the vocal tract is that we can make different sounds by changing the shape of the latter, by moving the tongue, the lips and even the larynx.

Consonants

Given the apparatus described above, there are several ways of produ-

cing speech sounds. Firstly, we can simply set the vocal cords vibrating and maintain a steady sound such as ‘aaaah’ or ‘ooooh.’ Or we can produce a very short-lived explosive sound such as ‘p’ or ‘t’, and another important type of sound is illustrated by ‘f’ or ‘s’, when we force air through a narrow opening to cause a

Sounds and suprasegmentals

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Table 1 IPA transcription for the English consonants

pay

[p]

far

[f]

boy

[b]

vie

[v]

thin

[θ]

though

[ð]

tea

[t]

sew

[s]

do

[d]

zip

[z]

chair

[ʧ]

show

[ʃ]

jar

[ʤ]

pleasure

[ʒ]

cow

[k]

go

[g]

her

[h]

me

[m]

war

[w]

now

[n]

low

[l]

ray

[ɹ]

you

[j]

hang

[ŋ]

hissing sound. Sounds such as ‘p’, ‘t’, ‘f’ and ‘s’ are called consonants, while those like ‘aaaah’ or ‘ooooh’ are vowels. The basic list (or inventory) of consonants in English is given in table 1. In all cases except for [ŋ] in hang and [ʒ] in pleasure, the consonant is at the beginning of the accompanying word – [ŋ] and [ʒ]

do not occur word-initially in English. As will be apparent, in many cases the IPA symbol, written between square brackets, is identical to the ordinary printed symbol. The reasons for laying out the table in this manner will become clear from the subsequent discussion.

Let’s begin by considering the sounds [p] and [f]. These differ from each other in their manner of articulation. The [p] sound is produced in three phases. Firstly, we shut off the vocal tract completely by closing the lips. Then, we try to force air out of the lungs. However, this air is prevented from escaping because of the closure and this causes a build up of pressure inside the mouth. Then, we suddenly open the lips releasing this pressure, and the result is an explosive sound that lasts for a very short time. Such sounds are called plosives, and the English plosives are [p b t d k g].

The production of [f] is quite different. Here we allow a small gap between the top teeth and the bottom lip and then force air through this gap. When air at high pressure is forced through a narrow opening, it sets up friction which causes a noise.

Sounds produced in this way are therefore called fricatives. The English fricatives are [f v θ ð s z ʃ ʒ h]. The initial consonants of chair and judge are complex sounds, which begin as plosives and end as fricatives. They are known as affricates and the IPA symbols [ʧ] and [ʤ] make their complex character clear.

The remaining sounds in table 1 fall into two groups. Firstly, consider the sounds [m n ŋ]. These are produced by allowing the nasal cavity to resonate.

Normally, the nasal passages are separated from the mouth and throat by a small

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sounds

piece of flesh, the velum (also sometimes called the soft palate), which is the backward continuation of the roof of the mouth (see figure 4). When the velum is lowered, air can pass through the nose. For instance, if we close the lips as if to produce a [b] and then lower the velum, the air from the lungs will no longer be trapped but will pass through the nose and set up vibrations there. This is how [m]

is produced, and sounds such as [m n ŋ] are called nasals. The other remaining group of sounds is [l ɹ w j] and we shall describe how they are produced after we have looked at the other sounds in more detail.

Consonants are distinguished by more than just their manner of articulation.

The sounds represented by [p t k] are all plosives, but these symbols represent different sounds. To understand the relevant distinctions here, we need to know something about the internal shape of the vocal tract, and figure 5 contains a cross-sectional view showing the way in which [m] is produced – for [p, b], the velum would be raised. The three sounds [p, b, m] are all formed by bringing the lips together, and they are referred to as bilabial sounds. By contrast, the sounds

[t d n] are made by placing the tip of the tongue against the gum ridge behind the upper teeth; this ridge is called the alveolus or the alveolar ridge and so [t d n] are called alveolar sounds. This articulation is illustrated for [n] in figure 6. Many Figure 5 Cross-section of the vocal tract, illustrating the articulation of [m]

Figure 6 Cross-section of the vocal tract, illustrating the articulation of [n]

Sounds and suprasegmentals

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Figure 7 Cross-section of the vocal tract, illustrating the articulation of [ŋ]

languages (e.g. French, Spanish, Russian) use sounds which are slightly different to the [t d n] we find in English. Speakers of these languages place the tip of the tongue against the upper teeth themselves rather than the alveolar ridge and this produces a dental sound. If we need to distinguish dentals from alveolars, we can use special IPA symbols [t̪ d̪ n̪] to refer to the dentals. Different again are [k g ŋ].

To produce these, we use a different part of the tongue, the body or dorsum, which is brought against the velum as illustrated for [ŋ] in figure 7. These sounds are known as velars and the descriptions we have introduced here give us the place of articulation of the sound.