The subsidiary (второстепенный) variants of the phoneme

In the word fact the sound [k] lacks two of the characteristic features of the principal variant of the English phoneme [k]: it has no plosion and, consequently, no aspiration. Therefore, it is a plosionless subsidiary variant of the phoneme [k].

Subsidiary variants of a phoneme are those which lack one or more of these features of the principal variant, or have one or more of these features in a modified form.

A phoneme has different subsidiary variants as a result of several factors. It depends on whether it occurs at the beginning, in the middle or at the end of a syllable, a word or a sentence, before or after a vowel, or between vowels, in a stressed or an unstressed syllable, before or after a pause.

For example, the sound [t] in the word too is pronounced with the lips already rounded in anticipation of the following rounded vowel [u:]. This labialized subsidiary variant of the English phoneme [t] is the result of regressive adaptation affecting the position of the lips.

Assimilation

Process of speech is the process of transition from the articulatory work of one sound to the articulatory work of the neighbouring one. In the process of speech sounds are modified (изменяются).

Assimilation may affect:

the point of articulation (when the alveolar variants of the sounds t d n l s z are replaced by their dental variants under the influence of the following interdental sounds th, th (tenth, in them)

the active speech organ and the point of articulation (when the prefix con is followed by the consonants k and g, and it is stressed; in this case the forelingual n is replaced by its backlingual counterpart (аналог) in such words as congress, concrete)

the manner of the production of noise (when the constrictive fricative v occurs before occlusive nasal m – give me – gimmi; in rapid speech occlusive t,d occur before the same sound or constrictive j – did you?)

the work of the vocal cords (voiceless consonants may be replaced by voiced ones under the influence of adjacent voiced consonants – gooseberry – z b; under the influence of the voiced sound b in the world berry the voiceless sound s in the word goose became voiced; also voiced consonants may be replaced by voiceless under the influence of the adjacent voiced consonants)

the lips position (when labialized variants of the phonemes are used under the influence of the following bilabial sonorant w – twin)

the position of the soft palate (when nasal consonants influence oral ones – let me – lemmi)