Code-switching
【正确答案】：Code switching is the switch made by a speaker or writer from one language or language variety to another. A person may start speaking one language and then change to another. A speaker may also switch from the standard variety to a regional dialect, or from the occupational variety to the domestic variety. Code-switching can occur between sentences or within a single sentence, involving words or phrases or even parts of words. Two types of code-switching are usually identified: situational code-switching and metaphorical code-switching.
