Should we consider variation in interlanguage performance in second language acquisition?

According to Tarone and Liu, there are two points of views about interlanguage variation. One prefers to study language as idealized form and excludes the study of variation. The other studies language forms in relation to their use in context, including the study of variation. However, Tarone and Liu focus on the latter. Variationists, like Tarone and Liu, focus upon external interactions and L2 learner performance in a variety of social contests. For them, interlanguage variation across those contexts is importantly related to change in learner’s Interlanguage knowledge over time. So, according to their perspectives, variation is a source of information about the way in which interaction in different social contexts can influence both interlanguage use and overall interlanguage development.

In this article, Liu conducted a very interesting study. It was a 26-month longitudinal study of a Chinese boy named Bob. Liu observed Bob’s speaking in English with his pre-school peers and supervisory staff, his teachers in his primary school classroom, primary school peers, and the researchers. There are interesting results. Even though Bob had the same knowledge system of English at disposal, Bob’s use of his interlanguage varies in its general shape as he moves from one situation to another.. More specifically, in interaction with the teachers, Bob only used very simple English. In interacting with peers, he made more extensive use of his knowledge by producing more complex English. In interaction with the researcher, he made still more extensive use of the knowledge to the extent of attempting syntactic structures. In other words, Bob’s use of his interlanguage knowledge is affected by the different interactional contexts. So, he is performing his competence differently in these different interactional contexts.

And then, why Bob’s competence develops differentially depending on the different interactions? Lie suggested that the different interactions in which Bob engaged had an impact on his interlanguage development, not only in terms of the rate of that development, but also on the route of his interlanguage development. That is, different interactional contexts support different rates of development of particular interlanguage features. And also, external social demands can be so strong that they can cause an alternation in internal psychologically motivated sequences of acquisition.

Before reading this article, I had only believed innate forces in language acquisition. However, it was very narrow point of view. There are obviously not only internal innate forces but also contextual forces in second language acquisition. Therefore, now I understand that it is very important what circumstance the child learns his or her SLA.