Chapter 6. Modifications of English consonant sounds.

By assimilation we mean a modification in the articulation of a consonant under the influence of a neighboring consonant. The term assimilation may be used when two adjacent consonants influence each other and give as result a single new sound.
A. 5 types of assimilation
You remember by assimilation we mean a modification in the articulation of a consonant under the influence of neighboring consonant, other words that are the case when two adjacent consonants influence to each other and result a single new sound different from either of them.
Assimilation may be considered when we speak of assimilation:

1. affecting a) the point of articulation b) both the point of articulation and the active organs of speech.
2. affecting the manner of production of noise
3. affecting the work of vocal cords
4. affecting the lip position
5. affecting the position of soft palate.

1. Assimilation affecting a) the point of articulation takes place when the principal (alveolar) variants of the phonemes [t],[d],[n],[l],[s],[z] are replaced by dental variants if they adjacent to dental consonant phonemes [θ],[ð].
E.g.: tenth [ten θ ] in them [inðem] read this [ri:d ðis]
b) Assimilation affecting the active speech organ and the point of articulation takes place in the following cases:
In words with prefix - con - when it’s followed by the consonants [k],[g]: the forelingual alveolar [n] is replaced by the back lingual velar [η] if the prefix is stressed.
E.g.: congress [kάηgres]
There is NO assimilation if the prefix is unstressed – congratulation – [kəngrætjύlei∫n].
When [m] is standing before [f], [v] it’s assimilated to them. The principal bilabial variant is replaced by its labio-dental variant.
2. Assimilation affecting the manner of production of noise takes place in following case.
When constrictive noise fricative [v] is standing before the occlusive nasal sonorant [m] in the word connection between me and give, let, in rapid speech they are assimilated to [m].
E.g.: give me [gim mi] let me [lem mi]. In this case, we consider assimilation affecting not only the manner of production, but the position of the soft palate.
3. Assimilation affecting the work of vocal cords takes place in the following cases.
A) A voiceless consonant may be replaced by a voiced one under the influence of the adjacent voiced consonant. The voiceless [s] in goose [gu:s] is replaced by the voiced [z] in the compound noun gooseberry [gu:zbəri] under the influence of the voiced [b] in berry.
b) A voiced consonant may be replaced by a voiceless one under the influence of the adjacent voiceless consonant.
E.g.: used [ju:zd] the consonants [z] and [d] have been replaced by the voiceless consonant [s] and [t] in used to [ju:st tu].
The pronunciation is common even when no to follows.
Used they to live here? [ju:st ðei tə liv hiə]
c) When the vowel [i] in the verb form is [iz] is omitted in the rapid speech and [z] is replaced by [s] under the influence of the preceding voiceless consonant.
E.g.: What is this? - What's this?
d)The English sonorants [m],[n],[l],[r],[j],[w] are partly devoiced when they are preceded by the voiceless consonants [s],[p],[t],[k] E.g.: small, please, slow, try.
4. Assimilation affecting the lip position takes place when the phonemes [k], [g], [t], [s] are labialized and used under the influence of the following bilabial sonorant [w].
E.g.: quick [kwik] twenty [twenty] language [læ η gwidʒ].
5. Assimilation affecting the position of the soft palate takes place when nasal consonants influence oral ones.
E.g.: let me, give me.
Also in sandwich [sænwidʒ] kindness [kainess] grandmother [grænm Λ ðə] the consonant [d] influenced by preceding [n],then it changed to the consonant [n] and disappeared.
In handkerchief [hæ η kət∫if] the consonant [d] is changed under the influence to consonant [n] and then disappeared. The remaining [n] changed to [η] under the influence of [k]. In this word we observe assimilation affecting the active organ of speech and the point of articulation.

B. 3 degrees of assimilation.
Assimilation may be of three degrees: complete, partial, intermediate.
Assimilation is said to be complete when the articulation of the assimilated consonant fully coincides with articulation of the assimilating one.
E.g.: horse-shoe [hɔs su:]
Assimilation is said to be partial when the assimilated consonant retains its main phonemic features and becomes only partly similar in some feature of its articulation to the assimilating sound.
E.g.: the alveolar variants of the consonants [t],[d],[n],[l],[s],[z] are replaced to the dental under the influence of the consonants [θ],[ð]; the main phonetic features of the former are retained but their point of articulation is changed.
The degree of assimilation is said to be intermediate between complete and partial when the assimilated consonant changes into a different sound but does not coincide with the assimilating consonant.
E.g.: congress [ka η gres], where [n] is replaced by [η] under the influence of [g].
C. Assimilation may be of three types: progressive, regressive, double.
We concern the follow directions:
In progressive assimilation the assimilated consonant is influenced by the preceding consonant.
This can be presented by the formula A→B, where A is the assimilating consonant and B the assimilated consonant.
E.g.: place the fully voiced variant of the consonant phoneme [l] is assimilated to [p] and is replaced by a partly devoiced variant of the same phoneme.
In regressive assimilation the preceding consonant is influenced by the one following it.
E.g.: the voiced consonant [z] in news [nju:z] is replaced by the voiceless consonant [s] in the compound word newspaper [nju:speipə] under the influence of the voiceless sound [p].
In horse-shoe [hɔ: ∫∫ u: ] [s] in horse [hɔ:s] was replaced by the [∫] and become fully assimilated to [∫] in shoe [ ∫ u:]
In double assimilation two adjacent consonants influence each other.
E.g.: twenty [twenti], quick [kwik] the sonorant [w] is assimilated to the voiceless plosive consonants [t] and [k] becoming partly devoiced. In their turn, [t], [k] are assimilated to [w] and are represented by their labialized variants.
In rapid colloquial speech one more of double assimilation may take place in some close-knit groups.
E.g.: in the phrases don’t you can’t you [t] is immediately followed by [j] and influences on it thus [j] changes into [t∫].
As a result [dj] is replaced by [d∫]:
don’t you [doʊnt jʊ ] - [doʊnt ∫ʊ]
can’t you [kɑ:nt jʊ] - kɑ:nt ∫ʊ]
E.g.: When [j] is preceded by [d] the former disappears giving [d] tongue-front coarticulation. As a result [dj] is replaced by [dʒ].
did you [did jʊ][didʒʊ]
could you [kʊd ju][kʊdʒu]
6.2. Accommodation.
The modification in the articulation of a consonant under the influence of an adjacent vowel is called accommodation. In accommodation the accommodated sound does not change its main phonemic features and is pronounced slightly modified under the influence of a neighboring sound.
In modern English there are three main types of accommodation.
1. An unrounded variant of a consonant phoneme is replaced by its rounded variant under the influence of a following rounded vowel phoneme as at the beginning of the following words:
E.g.: unrounded variant of consonant phoneme:
tea [ti:] less [les] none [nΛn].
E.g.: rounded variant of consonant phoneme:
too [tu:] loose [lu:s] noon [nu:].
2. A fully back variant of a back vowel phoneme is replaced by its slightly fronted variant under the influence of the preceding mediolingual phoneme [j].
E.g.: f ully back variant of [u:]:
booty [bu:ti] moon [mu:n]
E.g.: fronted variant of [u:]:
beauty [bju:ti] music [mju:zic]
3. A vowel phoneme is represented by its slightly more open variant before the consonant [l].
E.g.: bed [bed] – bell [bel] ten [ten] - tell [tel]
6.3. In rapid colloquial speech certain words may lose some of their sounds (vowels and consonants). This phenomenon is called ELISION. Elision takes place both in words and at the boundaries.
E.g.: phonetics [founetiks] [f|netiks]
mostly [moustli] [mousli]
all right [ο :l rait] [o:rait]
next day [nekst dei] [neksdei]
Some rules for elision.
1. Elision occurs when [t], [d] appear in a consonant cluster.
E.g.: nex t d ay [nekst dei] – [t] is elided between [ks] and [d] "[neksdei]
E.g.: sto pped f or a lunch [stopt fɔ:] – [t] is elided between [p] and [f] " [stopfɔ:]
E.g.: rea ched Paris [rit∫t Pæris] – [t] is elided between [t∫] and [p]
E.g.: car ved st atuette [kɑ:vd stætʊ′et] – [d] is elidedbetween [v] and [st].
2. Complex consonant clusters are simplified.
E.g.: acts [ækts] can be simplified to [æks]
texts [teksts] " [teks]
the Si xth′s th rone [sikθs θr] " [siks θr]

3. [ə] – can disappear in unstressed syllables.
E.g.: po lice, ton ight, coll ective – [ə] is omitted in the first syllable
E.g.: int e resting, veg e tables – [ə] is not pronounced by many speakers, reducing the number of syllables in the word.
4. [v] is omitted in of, before consonants
E.g.: o f N ovember, o f t ime, o f m y.
The students must know all the forms of assimilation, accommodation and elision described above but must aim at careful colloquial style in his own speech and avoid using assimilations and elisions typical of rapid colloquial English.