This research paper aims to demonstrate the importance of the phonemic level in the making and development of the linguistic atlas, as sounds are the raw or basic material that makes up the language, and it is the first thing that scholars submit to their study by examination and analysis, and the phonemic level, like other levels, is subject to change and change from one dialect to another through Its manifestations are: substitution, dithering, acclamation, accentuation and intonation..This level has been addressed with modern and advanced techniques, programs and special machines, and it has been studied in audio laboratories and special workshops, which provides us with accurate results and more standard judgments. Laboratory linguistic studies have also been useful in determining the physical characteristics of the linguistic voice, within the linguistic structure, and the influence that occurs in it between the sounds, and in this research the phenomenon of substitution will be addressed as one of the phonological phenomena in the dialect of the Al-Tayebat region

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