Chapter 1 the main directions in the study of sound

CHAPTER 2 THE FUNCTIONAL ASPECT OF SPEECH SOUNDS
2.1.Phonology.Methods of phonological investigation.
S.F. Leontyeva states that phonetics studies speech sounds as articulatory and acoustic units, phonology investigates them as units, which serve communicative purposes. Phonetics and phonology are closely connected. The unit of phonetics is a speech sound, the unit of phonology is a phoneme. The phoneme is the smallest unit of the language system. Phonemes can be discovered by the method of minimal pairs (commutation test or the method of substitution), which consists in finding pairs of words which differ in one phoneme. For example, ban – fan is a
pair of words distinguished in meaning by a single sound change. Two words of this kind are termed “minimal pair”. It is possible to take this process further and we can also produce can – ran – man – it is a minimal set. To establish the phonemes of the language the phonologist tries to find pairs that show which sounds occur or do not occur in identical positions. The method of minimal pairs helps to identify 24 consonant phonemes and 20 vowel phonemes in the phonological system of the English language. The phonemes of a language form a system of oppositions, in which any one phoneme is usually opposed to any other phoneme in at least one position, in at least one minimal pair. If the substitution of one sound for another results in the change of the meaning, the commuted sounds are different phonemes, speech sounds, which are phonologically significant. The statistical method is also used in phonology. Its aim is to establish the frequency, probability and predictability of occurrence of phonemes and their allophones in different positions.
Phonology is the study of the sound system of a language, including the patterns and rules that govern the use of speech sounds. There are several methods of investigation used in phonology, including:

1. 
   Phonemic analysis: This method involves identifying the phonemes, or smallest units of sound, that are used in a language. Phonemic analysis is often done by examining minimal pairs, which are words that differ by only one phoneme. For example, in English, the words "cat" and "bat" are minimal pairs because they differ by only one phoneme (/k/ versus /b/).
   
2. 
   Distributional analysis: This method involves analyzing the distribution of phonemes in a language, or where they occur in relation to other phonemes. For example, in English, the phoneme /p/ occurs only at the beginning of syllables, while the phoneme /b/ occurs only at the beginning of words or after a nasal consonant.
   
3. 
   Contrastive analysis: This method involves comparing the phonemes of two or more languages to identify similarities and differences. Contrastive analysis can help identify which phonemes are distinctive, or used to distinguish between different words, in a particular language.
   
4. 
   Morphophonemic analysis: This method involves examining how phonemes change when they are combined with other sounds in a language. For example, in English, the final sound in the word "cat" changes to /s/ in the plural form "cats."
   
5. 
   Natural classes: This method involves grouping phonemes into natural classes based on shared features, such as place of articulation, voicing, or manner of articulation. Natural classes can help identify patterns in the distribution of phonemes in a language.
   

Overall, these methods of investigation in phonology help linguists understand the structure and function of the sound system in a particular language, and how it is used to convey meaning.