Language fossilisation

Interlanguage fossilization is a phenomenon of second language acquisition (SLA) in which second language learners develop and retain a linguistic system, or interlanguage, that is self-contained and different from both the learner's first language and the target language. This linguistic system has been variously called interlanguage, approximative system, idiosyncratic dialects, or transitional dialects.

According to Corder this temporary and changing grammatical system, interlanguage, which is constructed by the learner, approximates the grammatical system of the target language. In the process of second language acquisition, interlanguage continually evolves into an ever-closer approximation of the target language, and ideally should advance gradually until it becomes equivalent, or nearly equivalent, to the target language. However, during the second language learning process, an interlanguage may reach one or more temporary restricting phases when its development appears to be detained. A permanent cessation of progress toward the target language has been referred to as fossilization. This linguistic phenomenon, interlanguage fossilization, can occur despite all reasonable attempts at learning. Fossilization includes those items, rules, and sub-systems that second language learners tend to retain in their interlanguage, that is, all those aspects of interlanguage that become entrenched and permanent, and that the majority of second language learners can only eliminate with considerable effort. Moreover, it has also been noticed that this occurs particularly in adult second language learners' interlanguage systems.

Selinker suggests that the most important distinguishing factor related to second language acquisition is the phenomenon of fossilization. However, both his explanation that "fossilizable linguistic phenomena are linguistic items, rules, and subsystems which speakers of a particular native language will tend to keep in their interlanguage relative to a particular target language, no matter what the age of the learner or amount of explanation or instruction he receives in the target language" and his hypotheses on interlanguage fossilization are fascinating in that they contradict our basic understanding of the human capacity to learn. How is it that some learners can overcome interlanguage fossilization, even if they only constitute, according to Selinker, "a mere 5%", while the majority of second language learners cannot, "no matter what the age or amount of explanation or instruction"? Or is it perhaps not that they cannot overcome fossilization, but that they will not? Does complacency set in after second language learners begin to communicate, as far as they are concerned, effectively enough, in the target language, and as a result does motivation to achieve native-like competence diminish?

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