Children seem to acquire language with little to no effort and master it within a few years. Second language acquisition, however, typically requires years of study that may never result in complete mastery. Why does this dichotomy exist? One approach that researchers use to answer that question is error analysis.
Error Analysis
In her text, Introducing Second Language Acquisition, Muriel Saville-Troike comments that learners' errors are "sources of insight into the learning processes" (2006, p.38). The mistakes that people make when learning language reveal patterns of second language development and differences between first and second language acquisition.
Two closely related types of errors that occur in second language learning are code switching and code mixing.
Code Switching
Code switching occurs between sentences. The speaker will finish a sentence in one language but switch to another language for the following sentence, as in this example:
Spanish/English Speaker:
"Le dije que no queria comprar el carro. He got really mad."
English Translation:
I told him I didn’t want to buy the car. He got really mad.
Code Mixing
Code mixing occurs at boundaries within the sentence. Despite the shift in language, code mixing usually occurs with no pause or interruption to the speech stream. This type of language shift usually occurs at the clause, phrase, or word level of a sentence, as in this example:
Spanish/English Speaker:
"Abelardo tiene los movie tickets."
English Translation:
Abelardo has the movie tickets.
What Code Switching and Code Mixing Reveal about Second Language Learning
Studies have shown that both fluent bilinguals and non-fluent language learners may use code switching. Code mixing, on the other hand, is indicative of truly fluent, proficient bilingual speakers and is less likely to be observed in less fluent bilinguals or in late second language learners (Becker 1997, p.7; Lipski 1985, p.2). One explanation for this difference is that code mixing requires mastery of two linguistic systems and the ability to control those systems simultaneously while speaking, since it occurs in language units that are smaller than a sentence.
From observing errors such as code switching and code mixing, researchers can ask questions about the patterns of the errors themselves with the hope of establishing a developmental path for second language acquisition, or SLA. For example, when a speaker code switches, is it from the first language (L1) to the second language (L2) or vice versa? And when speakers mix, are they inserting L2 words into first language sentences? Do the error patterns and the frequency of switching and mixing change over time?
Second language learning is more difficult and takes longer than first language acquisition. Using research methods such as error analysis, researchers hope to discover why this is so and to map out the learning processes that second language learners go though.
References
Saville-Troike, Muriel. (2006). Introducing Second Language Acquisition. Cambridge: Cambridge University Press.
Becker, K.R. (1997). "Spanish/English Bilingual Codeswitching: A Syncretic Model." The Bilingual Review, 22 (1), 3-30.
Lipski, J.M. (1985). Linguistic Aspects of Spanish-English Language Switching. Arizona: Center for Latin American Studies, Arizona State University.