What process occurs when a speaker alternates between languages in conversation?

The process described in the question is known as code-switching. This refers to the practice of alternating between two or more languages or language varieties within a conversation or discourse. It typically occurs among bilingual or multilingual speakers who navigate different linguistic environments and switch languages based on context, audience, or topic of conversation.

Code-switching is a natural and common phenomenon in multilingual communities, reflecting the speaker's identity and cultural background. It allows individuals to express nuanced meanings or fit into various social or linguistic contexts more effectively.

Language shift involves a gradual change in the language spoken by a community, often moving towards a dominant language over generations, which is different from the momentary and situational use of multiple languages in code-switching. Translation refers to converting text or speech from one language to another, which is also distinct from the informal, spontaneous practice of code-switching. Bilingualism, on the other hand, describes a person's ability to speak and understand two languages fluently, but it doesn't inherently involve alternating between them in conversation.