CODESWITCHING
Code-switching
In linguistics, code-switching occurs when a speaker alternates between two or more languages, or language varieties, in the context of a single conversation. Multilinguals—speakers of more than one language—sometimes use elements of multiple languages when conversing with each other. Thus, code-switching is the use of more than one linguistic variety in a manner consistent with the syntax and phonology of each variety.The above text is a snippet from Wikipedia: Code-switching
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