An interlanguage or, more explicitly, interim language is an emerging linguistic system that has been developed by a learner of a second language (or L2) who hasn't become fully proficient yet but is only approximating the target language: preserving some features of their first language (or L1) in speaking or writing the target language and creating innovations. An interlanguage is idiosyncratically based on the learners' experiences with the L2. It can fossilize in any of its developmental sta… (More on Interlanguage)