Hear it with customers at work all the time - arguments, conversations, phone calls, all can wind up a mix of languages. Yeah, happens in real life.
When hanging out with my Latino friends we are speaking 100% Spanish.
When I need to be excused, I will say in my best Terminator accent, “I will be back”.
Everyone understands it. Due to the popularity of the flick, it may be universal.
My mom used to do this all the time, only it was German/English. I remember being afraid to identify a spatula in class because I thought it might be the German word instead of the English word. I learned a lot about plants from my Oma and knew the word petersilie before I knew the word parsley.
In my teen years a large number of remarks addressed to me started with "Unser Gott im Himmel " then preceded to describe my various deficiencies in excruciating detail in English.
I learned the word malaka from the club scene in Weird Science.
Totally, I do it every day
I work with a lot of Hispanics and we do it todos los dias. It’s funny that there are certain words we always say in Spanish, and sometimes there is no rhyme or reason-- often the Spanish word is longer than the English word, for instance. And although we sometimes use Spanish words we don’t want others to understand, that’s a tricky proposition since so many people speak Spanish here.
Thanks! You saved me a lot of typing. 
I’m curious as to why the OP thinks that this would be uncommon. Not challenging, just curious.
I guess (answering for the OP) it seems odd because much of the time it requires some conscious effort to switch languages: in most cases the languages’ grammar doesn’t lock together trivially.
My first language is English and second is Mandarin. In most cases a sentence started in one of those languages wouldn’t be possible to trivially finish in the other, because of word order differences, or details like whether I need a spoken question mark.
And also it feels like a TV convention: to just throw in a few words the viewer will know to establish the chracter’s nationality or family background.
But in fact I do often switch languages when speaking to people who know both, because there are some expressions that are difficult to translate.
In my office (in San Francisco) we have quite a few Tagalog speakers, and some Spanish speakers as well. I hear conversations going back and forth between languages every day. My best friend will be talking to me in English, and turn to a Spanish-speaker and say something in Spanish (maybe throwing in some English if it’s work-related), and then answer the phone and speak either English or Spanish depending on who is on the line, and then turn back and ask me a question in English, or ask the Spanish-speaker a question in Spanish. The good news is that last week I needed to deal with a Spanish-speaker on the phone who spoke very poor English, so I brought my friend in to translate and was finally able to resolve an issue after weeks of trying.
Happens with bilingual Yiddish/English speakers. It also happens trilingually with Hebrew/Yiddish/English speakers.
Also, FWIW, Jews who don’t necessarily speak either Yiddish or Hebrew fluently use many Yiddish and Hebrew words with other Jews that they wouldn’t use with gentiles, so the it’s “synagogue” when you are talking to a gentile, but “shul” to another Jew, and “Passover” to a gentile, and “Pesach” to another Jew. Something is “effed up” to a gentile, “farkockteh” to a Jew. The Temple in Israel, if you discuss it with a Jew, is the “beit hamikdash.” I grew up in a household like that. I didn’t even know the English words for certain body parts until I was about seven. I’m not sure to what degree a gentile with little knowledge of Judaism would be scratching their heads listening to a conversation like that, and how much is obvious from context.
Sometimes when you have two imperfect language users, each one will use the others language, because you get the best change of being understood. A lot of times, when I was just learning sign language, a Deaf person who spoke well, would just talk to me, but I would sign to them. Also, when I had a couple of French penpals in high school, they wrote to me in English, and I wrote to them in French.
One more data point: hearing people who know ASL well and use it on a regular basis often pepper their spoken conversation with signs, because sometimes one sign says something that would take several words. Sometimes also you can make jokes you couldn’t otherwise make.
Now, that’s not to say that the trope isn’t done for laughs, and not the way people actually talk. It’s be [Spanish] then just enough English to either provoke laughter or cause a misunderstanding, then [Spanish again], as opposed to Spanish food words, followed by “iPad app crashed,” then some swear word in Spanish, then an English recap of a conversation with a coworker that was originally in English.
My Spanish parents do this all the time, only with Spanish-Swedish instead of Spanish-English.
My relatives on my mom’s side are fluent in Spanish and English to varying degrees, and I’ve seen/heard them do it. Sometimes it’ll happen just for a few words (and honestly, if you live in Texas, Spanish and English have a lot of loaned words in each other’s garage even when you aren’t bilingual).
Similarly, I spent time studying Mandarin Chinese, and something I noticed in the classroom was that students who had studied other languages would switch back and forth based on which ever language offered up an appropriate word first (I’d accidentally switch to Spanish, another classmate would shift to French, we all tended to go back and forth between broken Mandarin and English). Our teachers would similarly switch between Mandarin and English, even when talking to each other (also leaving aside the fact that Mandarin borrows vocabulary like any other vernacular language does).
My wife and I have a household vocabulary that includes various canned phrases from Spanish, Mandarin, and Japanese peppered throughout, but it’s probably not really a straight example of what OP is talking about. She can’t speak Mandarin any better than I can speak Japanese, and neither of us are honestly any good at Spanish.
I’ve been in a few three-way conversations as the only gentile, and, while I’d never really noticed it before, this definitely does happen (U.S., all native English speakers).
Reminds me of the scene in What Did You Do In The War Dad?.
The German and Italian commanders meet for the first time. The German says “sprechen sie Deutsch?” and the Italian replies, “Nein, parla Italiano?”.
“Nein. Do you speak ze Englisch?”
“But of-a course!”
From then on, they communicate in accented English so that subtitles are unnecessary.
Actually, I’ve known married couples whose common language is neither of the person’s native languages. I know a couple who are Finnish and Hungarian whose common language is English, and a couple who are American and Italian whose common language is French (they ended up living in Switzerland, so French as the home language was normal, although when they had kids, the husband wanted his wife to speak English to them, because he thought it would be useful for them to know English).
In middle school, I had a bilingual Chinese-American friend who mostly spoke Mandarin to his parents, and English to the rest of us. One day, his mom called him into the other room to talk about something (chores, I think it was), and it was rapid-fire Mandarin back and forth until 'Aw mom! Can I do it tomorrow?" or something like that. I guess whining to your parents doesn’t translate quite so well into Mandarin.
Mrs. Yao actually spoke fine English- she worked in the cafeteria at school.
My Hispanic neighbor did this to me the other day. He and his wife pull into the parking lot outside our windows any time of day and start tapping the horn to get one or the other to come out. I went outside and called him out on it and he played dumb, switching back and forth between English and Spanish. A half hour later, he came over with his teenage son and had him interpret, but still would switch back and forth in speaking to me.
They denied it, I apologized, but we both know it is him. He had even helpfully pointed out his vehicle when I first went outside and yes, it is him.
But at least the honking has dropped off a lot. Except for 12:30 this morning when his wife came home. :smack:
Not only is code-switching common, it has its own rules, as described to me by a linguist who studied it. She was French Canadian but her English was unaccented with native or near-native fluency. One point I recall is that when a sentence with a switch is analyzed, both parts were invariably well-formed phrases in whatever language it was. So in switching between French and English (which she was studying in Montreal) you could not normally modify a noun in one of the languages by an adjective in the other because in French most adjectives follow the modified noun, while in English they precede. I guess English/German code switching is harder because of all the verb final and separable prefixes, but I am extrapolating here. Apparently Spanish/English code-switching is very common in NY.
Although not code switching, there is a town in Switzerland Biel/Bienne in which everyone is fully bilingual and the practice is that each native speaks his own language to any other native, so conversations in which the Bieler speaks German while the Biennois speaks French are exceedingly common.
yep. at my previous job, I sat near a co-worker who was Albanian. When she was talking on the phone to her kids, she was constantly switching back and forth.