Interlanguage

Interlanguage is the term for an ideolect that has been developed by a learner of a second language (or L2) who has not yet reached proficiency. A learner's interlanguage preserves some features of their first language (or L1), and can also overgeneralize some L2 writing and speaking rules. These two characteristics of an interlanguage result in the system's unique linguistic organization.

An interlanguage is idiosyncratically based on the learners' experiences with the L2. It can "fossilize", or cease developing, in any of its developmental stages. The interlanguage rules are claimed to be shaped by several factors, including L1-transfer, previous learning strategies, strategies of L2 acquisition (i.e., simplification), L2 communication strategies (i.e., circumlocution), and overgeneralization of L2 language patterns.

Interlanguage is based on the theory that there is a dormant psychological framework in the human brain that is activated when one attempts to learn a second language. Interlanguage theory is often credited to Larry Selinker, who coined the terms "interlanguage" and "fossilization." Uriel Weinreich is credited with providing the foundational information that was the basis of Selinker's research. Selinker (1972) noted that in a given situation, the utterances produced by a learner are different from those native speakers would produce had they attempted to convey the same meaning. This comparison suggests the existence of a separate linguistic system. This system can be observed when studying the utterances of the learner who attempts to produce meaning in their L2 speech; it is not seen when that same learner performs form-focused tasks, such as oral drills in a classroom.

Interlanguage can be variable across different contexts; for example, it may be more accurate, complex and fluent in one domain than in another.

To study the psychological processes involved one can compare the interlanguage utterances of the learner with two things:

It is possible to apply an interlanguage perspective to a learner's underlying knowledge of the target language sound system (interlanguage phonology), grammar (morphology and syntax), vocabulary (lexicon), and language-use norms found among learners (interlanguage pragmatics).

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