The term interlanguage was first coined and developed in the interlanguage theory published in 1972 under the authorship of Larry Selinker, a well known SLA theorist. Thisterm is used to refer to both the internal system that a learner has constructed at a single point in time and the series of interconnected systems that characterize the learner’s progress over time.Although, Selinker can be considered the father of interlanguage, the same phenomenon was described by other theorists, like Nemser (1971) and Corder (1971), but under different terms.
Interlanguageis based on the theory that there is a "psychological latent structure in the brain" which is activated when one attempts to learn a second language. Selinker points out five cognitive processesinvolved in interlanguage construction, or so called latent psychological structure:
1. Language Transfer: where some items, rules and structures of L1 can be transferred to production of L2.
e.g.Polish English learner can utter: *am at home - not mentioning the subject as in his L1 subject is indicated by the ending of the verb, therefore omitted)
2. Transfer of Training: when languageteaching creates interlanguage rules that are not of the L2 and which result in the way the learners were taught.
e.g. when teacher overuses utterances with the use of ¨he¨, which therefore discouragesthe use of ¨she¨.
3. Strategies of Second Language Learning
e.g. simplification, when for example the learner uses only one form of a verb
4. Communicative Strategies: when, for instance, thelearner omits grammatically redundant items in an utterance, producing ill-formed sentences.
e.g. *I saw beautiful girl. (omitting an ¨a¨ article).
5. Overgeneralization of L2 material: where thelearner tries to use L2 grammatical rules in the way there would not be used by a native speaker.
e.g. *What does she doing now?
To study the psychological processes involved one should compare the...