By John McWhorter, Ph.D., Columbia University
Many speakers use languages that are mixed in some way or another. One of the reasons for speaking a mix of languages could be imperfect acquisition of the language. Or, in a very different way, it is what is termed code switching–a more deliberate mixing of languages.

Incomplete Language Acquisition
An average person may be able to speak more than one language. But they may not be able to speak all the languages perfectly. The situation is that a whole lot of people start learning a language incompletely. That might start having an effect upon this language, and other elements from all these languages might start to flow in.
The world is full of this sort of incomplete acquisition. Take Australia, for example. There are these women who were brought from other groups, and they spoke other languages, but presumably they learn the language of their new group, to some extent.
They are human beings just like the rest of us; presumably they don’t learn it perfectly. Then the children hear that language, and they are hearing their mother’s version of the village language. Their mother’s version is not complete. She’s using some words from her language. The kids hear that. A lot of languages have been acquired and mixed in this way.
The way we tend to learn languages now, with a blackboard and poorly-written textbooks, and things like that—that’s brand new. The idea of “je suis, tu es, now recite after me” is not the way languages are generally learned around the world. The way we are doing that now is kind of a print/educational revolution phenomenon.
This is a transcript from the video series The Story of Human Language. Watch it now, Wondrium.
The First Step to Language Mixing
There are some languages in the world that are so mixed that you can no longer call them a version of Language A or a version of Language B. They are just hybrids. Kind of like a mule is neither a horse nor a donkey. The way these languages begin—before we get to those languages—is with something we are more familiar with.
This is something called ‘code switching’ by linguists, but in the real world is often termed “mixing-the-languages-all-together-and-I-know-I-shouldn’t-do-that.” But it is actually something that is common in the world. This is where speakers are regularly alternating between two languages in the course of a conversation.
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The ‘Nuyorican’ of New York

For example, there is what is sometimes called ‘Nuyorican’. If you listen to Latinos in New York, say on the train, you could hear some of them speak a sentence and a half in Spanish, and then they would switch to English and then back to Spanish.
People may think that it is really a shame that these people don’t know either one of those languages well enough to actually use one all the time. Others may think of it as a kind of linguistic scourge in New York City; a condition where people haven’t learned either language—English or Spanish—well.
But this is not a scourge, nor is it really incomplete language acquisition or competence. It has been studied and it is ‘code switching’.
Actually, people like this speak Spanish and English equally well, and what they’re doing is indexing a kind of bi-cultural identity. So if somebody in that setting wanted to say, “Why make Carol sit in the back so that everybody has to move so that she gets out?” That would be an ordinary English sentence. A person like this might say, “Why make Carol sentarse atras para que everybody has to move para que se salga?” You hear people doing that in New York all the time. Back and forth, back and forth.
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Code Switching Marks Bicultural Identity
It’s interesting. If you study it, you find that it has a grammar. You can’t just switch anywhere. You can’t switch in the middle of a word. There are certain ways you can tack endings on and some ways that you cannot. It’s very systematic. There’s a whole cottage industry in linguistics right now trying to figure out precisely what the system is. In other words, it is a real academic topic.

It is done all over the world. It is not just Spanish and English, but generally between any two languages, especially where one is the dominant one in society and then there is one that is loved more intimately. People will switch in between. People are doing it between French and Wolof in Senegal, for example.
So it’s a general phenomenon. And usually the more intimate the switching is, the more bi-cultural the identity that is indexed. So people switching in the middle of the sentence—like, “Why make Carol sentarse atras para que everybody has to move para que se salga?”— indicates more of a bicultural identity than just switching between sentences.
Code Switching as a Step Towards a New Language
So when you see someone code switching, what you are seeing is someone who is truly melting into the new society while retaining a part of their identity. For many people, that is considered the ideal thing.
So code switching can be seen as healthy. But what code switching actually is—so much of what you see in the present is really just a step along the way towards something else; it’s part of a cline. This is the beginning of what can be a whole new kind of language.
Common Questions About Incomplete Language Acquisition and Code Switching
Incomplete language acquisition is when a group of people learn another language by speaking it on daily basis. In this process, they tend to retain elements of their own language and acquire partial elements of the new language they are learning.
The term code switching means a situation where speakers are regularly alternating between two languages in the course of a conversation.
Nuyorican is the word used for the code switching between Spanish and English that is common in New York. This is spoken by people proficient in both languages.
Code switching is an indicator of a plural cultural identity. The more intimate the code switching, the more bi-cultural the identity which is being claimed or indexed.