Assimilation is a phonetic process when two adjacent consonants within a word or at word boundaries influence each other in such a way that the articulation of one sound becomes similar or even identical with the articulation of the other one.

Assimilation may affect: the work of an active organ, e.g., congress; the point of articulation as in, e.g., congratulate; the manner of production of noise, e.g., in let me as [ ˈ lem ɪ ]; the work of vocal cords, e.g., gooseberry; the lip position, e.g., twenty; the position of the soft palate, e.g., sandwich.

When the articulation of a sound is changed under the influence of the neighbouring sound in the course of language development assimilation is historical. Contextual assimilation takes place when the articulation of a sound changes under the influence of the neighbouring sounds in rapid colloquial speech or in the living language.

DEGREES OF ASSIMILATION Assimilation Complete When the articulation of an assimilated consonant fully coincides with that of an assimilating one. Intermediate when an assimilated consonant changes into a different sound, but doesnt coincide with the assimilating consonant. Partial when an assimilated consonant retains its main phonetic features and becomes only partly similar in some features of its articulation to an assimilating sound.

TYPES OF ASSIMILATION Assimilation Progressive an assimilated consonant is influenced by the preceding consonant. Double adjacent consonants influence each other. Regressive an assimilated consonant is influenced by the following consonant.