Interlanguage as an Outcome of Bilingual Linguistic Systems in Contact

Most previous studies of interlanguage (IL) relate IL performance errors in second language (L2) learning to the developing IL system itself. Though in such studies, language transfer is regarded as one of the processes responsible for IL development, little attention has been paid to the relationship and interaction between learners’ first language (L1) and target language (TL). This study assumes that IL, as a developing linguistic system, involves several linguistic systems, such as learners’ L1, learners’ TL, and learners’ currently acquired L2, and such linguistic systems are in contact in learners’ target-oriented speech production, each contributing different amounts to the developing IL system. This study further assumes that the nature and activity of the bilingual mental lexicon may play a significant role in IL development. As claimed in this study, the bilingual mental lexicon contains language-specific ‘lemmas’ (i.e., abstract entries in the mental lexicon about individual lexemes), and such lemmas are in contact in IL production. Thus, IL performance errors are viewed as consequences of ‘lemma transfer’ of learners’ L1 abstract lexical structure. The lexical structure is ‘abstract’ because it contains three abstract levels of linguistic organization: lexical-conceptual structure, predicate-argument structure, and morphological realization patterns. This study treats IL as an outcome of bilingual linguistic systems in contact at an abstract level. IL performance data are analyzed to test the hypothesis that the developing IL system is driven by an incompletely acquired abstract lexical structure of the TL, and IL development is always a predictable and target-oriented process.