An introduction to sociolinguistics

 
2015
The Equivalence Constraint suggests that code-switching can occur only in positions where 
"the order of any two sentence elements, one before and one after the switch, is not excluded in 
either language." Thus, the sentence: "I like you porque eres simpático" ("I like you because you 
are nice") is allowed because it obeys the syntactic rules of both Spanish and English. The 
Functional Head Constraint is another constraint-based theory. It holds that code-switching 
cannot occur between a functional head (a complementizer, a determiner, an inflection, etc.) and 
its complement (sentence, noun-phrase, verb-phrase). 
Although constraint-based theories are widely discussed, linguists continue to debate 
apparent counter-examples to each proposed constraint. 
The constraint-free approach views explicit reference to code-switching in grammatical 
analysis as tautological, and looks to explain specific instances of grammaticality in code-
switching in terms of the unique contributions of the grammatical properties of the languages 
involved in the construction of interest. Jeff McSwan characterized this approach with the 
research program refrain, "Nothing constrains code switching apart from the requirements of the 
mixed grammars." This approach focuses on the repudiation of any rule or principle which 
explicitly refers to code switching itself. 
Working within a speech production framework advocated by Willem Levelt, Carol 
Myers-Scotton has proposed the Matrix Language Frame (MLF) model of code-switching which 
distinguishes between the roles of the participant languages. Some theories, such as the Closed-
class Constraint, the Matrix Language Frame model, and the Functional Head Constraint, which 
make general predictions based upon specific presumptions about the nature of syntax, are 
controversial among linguists positing alternative theories. In contrast, descriptions based on 
empirical analyses of corpora, such as the Equivalence Constraint, are relatively independent of 
syntactic theory, but the code-switching patterns they describe vary considerably among speech 
communities, even among those sharing the same language pairs. 
Scholars use different names for various types of code-switching. Intersentential switching 
occurs outside the sentence or the clause level (i.e. at sentence or clause boundaries). It is 
sometimes called "extra-sentential" switching Whereas, Intra-sentential switching occurs within 
a sentence or a clause. Tag-switching is the switching of either a tag phrase or a word, or both, 

---

AN INTRODUCTION TO SOCIOLINGUISTICS