We know code switching is not a new phenomenon. And we know educated, fluent speakers code switch; it's not something that pops out of the mouths of people who aren't fluent in a given language. So why do people do it? For many, it's inadvertent. Take the example of Stuart Horwitz, a native English-speaker fluent in French, and his husband, Xavier Saint-Luc, a Frenchman fluent in English. Horwitz and Saint-Luc always converse with each other in French. But Horwitz says when he's angry with Saint-Luc, he automatically starts yelling in English.
"English is a more emotional language for me, since it's my native language," he says. "And I don't have to think when I express myself. It also seems more powerful to express my anger in English."
Laughs Saint-Luc,"When he starts talking English, I know it's bad!"
Saint-Luc also notes that when conversing with Horwitz in French, he uses the English word for items that have strong connotations of America for him. "When we're [staying at our home] in the U.S., I often buy sunflowers," he says, "and I have to ask the clerk for 'sunflowers.' So whenever we're speaking in French and talking about the sunflowers, I use the English word for them, not the French."
More proactively, some people code switch to fit in with a group, morphing their speech to sound more like those around them. An example of this would be the Georgian native previously mentioned, who started saying "y'all" on her visit back home. Others code switch in the hopes it will make people like them or look kindly upon them. Many service-industry employees say they'll adopt a Southern accent because they typically receive better tips when they do. Customers are also generally friendlier to them when they sprinkle "y'alls" throughout their speech [source: Thompson].
While some people code switch to fit in, others toss in foreign words or phrases to show others they know a second language. Or to sound cool. Certain words or phrases simply sound better in another language or better express your emotion; for instance, "C'est la vie!" ("That's life!") [source: Nortier]. And some people code switch because they want to say something they hope no one but the person they're talking to will understand. But beware: My English-speaking friend and I once slipped into our high-school-level Spanish to describe a hot guy who entered the room — and he answered us back in that language. Oops.