codeswitch

Code-switching refers to the systematic alternation between two or more languages or language varieties within a single communicative event. It can occur at different granularity levels, including intra-sentential switches (within a sentence), inter-sentential switches (between sentences), and tag switches (at clause or phrase boundaries). In everyday use, individuals may mix languages in a way that creates new, hybrid expressions.

Code-switching is common in multilingual communities and is distinct from borrowing or pidgin formation. It serves multiple functions: filling lexical gaps, quoting or reporting speech, signaling identity or solidarity, matching the social setting or addressee, and shifting to a more or less formal register. It can also reflect pragmatic purposes, such as emphasis or topic change.

Linguists distinguish several types. Intra-sentential switching integrates items from a second language into the morphosyntactic frame of the first; inter-sentential switching occurs at sentence boundaries; tag switching adds a short tag from one language to a sentence in another. The phenomenon has been analyzed with theories such as Poplack’s equivalence constraints, which note that switches tend to conform to the grammar of the surrounding language, and Myers-Scotton’s Matrix Language Frame, which posits a dominant matrix language providing the syntactic framework with embedded content from another language.

Code-switching is studied in sociolinguistics as a window into language contact, identity, power, and community norms. It has practical implications for education, language policy, and natural language processing, where recognizing and modeling bilingual speech improves understanding and accessibility.