Positional and combinative changes of vowels and consonants in connected speech.

Subsidiary variants of English phonemes appear due to the positional and combinative modifications of vowels and consonants in connected speech.

Thus, no matter whether a vowel is originally long or short, the length of its variants differ depends on whether it is pronounced with the rising, falling or falling-rising tone, whether it occurs in a word-final position, before a voiced or voiceless consonant, in a polysyllabic or monosyllabic word, in a stressed or unstressed position.

The appearance of variants of vowel phonemes is also determined by the process of reduction, or weakening of a sound in unstressed position. In English there are certain words which have two forms of pronunciation: strong, (or full form) and weak (or reduced form). These words include form words (articles, prepositions, modal and auxiliary verbs, conjunctions, particles), personal, possessive and relative pronouns. There are three degrees of reduction:

1. Quantitative reduction – when the length of the vowel is reduced and the subsidiary variant of the same phoneme takes its place (ex. the apple [ ði. æpl]).

2. Qualitative reduction – when the quality of a vowel changes and the allophone of one phoneme is replaced by the allophone of another phoneme (ex. the pen [ ðə pen]).

3. Zero reduction – when the vowel is omitted, or, in other words, when the zero variant of the phoneme is used (ex. D’you live in London).

The appearance of variants of vowels is determined by the process of accommodation – adaptation of vowels to adjacent consonants. For instance, a fully back variant of a phoneme [u:] is replaced by its slightly fronted variant under the influence of the preceding mediolingual consonant [j] (beauty, music). A vowel phoneme is represented by its slightly open variant before the dark [l] (bell, tell).

The appearance of variants of consonants is determined by the process of assimilation when the articulation of one sound influences the articulation of a neighbouring sound making it similar or even identical to itself. The consonant that influences a neighbouring one is called the assimilating. The consonant which is under the influence of a neighbouring one is called the assimilated.

The process of assimilation has three degrees:

1) complete - when the articulation of the assimilated consonant fully coincides with the assimilating one, in other words, when the allophone of one consonant is replaced by the allophone of a neighbouring consonant: (ex. horse-shoe [ho:∫∫u:]

2) partial – when the assimilated consonant still has some of its main phonemic features, in other words, when the subsidiary variant of the same phoneme appears (ex. twins, place, cry).

3) intermediate - when the assimilated consonant changes into a different phoneme which does not coincide with the assimilated one, in other words, when the allophone of one consonant is replaced by the allophone of some other consonant (ex. goose [gu:s] + berry = gooseberry [gu:zbəri]; news [nju:z] + paper = newspaper [nju:speipə].

According to the direction assimilation may be:

1) progressive - when the assimilated consonant is influenced by the preceding one (ex. speak);

2) regressive - when the assimilated consonant is influenced by the following one (ex. little);

3) reciprocal, or double - when the consonants influence each other (ex. twilight).

Due to the cases of assimilation the following subsidiary variants of consonants appear:

Dental variants of the alveolar consonants [l, n, t, d, s, z] appear under the influence of interdental consonants [θ, ð] (ex. tenth, at the table, read this).

Non-plosive variants of stop consonants [p, t, k, b, d, g] appear when two plosives occur together or when plosives are followed by affricates [d 3, t∫] (ex. sit down, black chair).

Nasally exploded variants of the stop consonants [p, b, t, d, k, g] appear before the nasal sonorants [m, n] (ex. garden, help me).

Laterally exploded variants of the consonants [p, b, t, d, k, g] appear before the lateral sonorant [l] (ex. that lesson, middle).

Labialized variants of consonants appear before labialized consonant [w] of the same word. (ex. dwell)

Partially devoiced variants of the sonorants appear after syllable-initial voiceless consonants (ex. try, clean).

Unaspirated variants of the aspirated phonemes [p, t, k] appear before an unstressed vowel and after [s] (ex. speak, skate, style).

Post-alveolar variants of the alveolar consonants [t, d, n, 1] appear before post alveolar consonant [r] (ex. try, Henry, already).

Alveolar variant of the post-alveolar consonant [r] appear after interdental consonants [θ, ð] (ex. three, with Russian).

The appearance of variants of consonants is also determined by the process of accommodation of consonants to the adjacent vowels. The consonant [l], for instance, has two variants in English: clear variant [l], which occurs before vowels and [j] (ex. lesson [lesn], value [vælju:]), and dark variant[l], which occurs before consonants and in word-final position (ex. children [t∫ildren], bell [bel]). An unrounded variant of a consonant is replaced by its rounded variant under the influence of the following rounded vowel [o, o:, u, u:] (ex. too [tu:], call [ko:l].

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