interlanguage

Interlanguage is the evolving linguistic system that a learner constructs as they acquire a second language. The term, introduced by Larry Selinker in 1972, describes the learner’s current hypotheses about the target language, shaped by the native language and instructional context. It lies between the learner’s first language and the ultimate L2 competence and is not simply incorrect language but a distinct, developing system with its own patterns.

Interlanguage is characterized by systematicity, variability, and potential fossilization. Errors reflect productive generalizations and the learner’s attempts to reconcile L1 influence with L2 rules. Selinker identified several factors contributing to interlanguage development, including language transfer from the first language, transfer of training from classroom instruction, learner strategies for acquiring and using the language, and the overgeneralization of target-language rules. The learner’s interlanguage continually changes as new input, feedback, and practice are encountered.

The concept highlights that language learning is a dynamic process rather than a straightforward progression from L1 to L2. Interlanguage can display multiple variants depending on context, interlocutor, and topic, illustrating the learner’s ongoing hypothesis testing about how the language works. Over time, with sufficient exposure and corrective, supportive input, interlanguage may converge toward the target language, though it can also stabilize at a stage in which progress slows or halts (fossilization).

In research and pedagogy, interlanguage provides a framework for analyzing learner errors, understanding the SLA process, and informing instructional approaches. It encourages focus on meaningful communication, comprehensive input, and feedback that guides development without demanding unattainable perfection.