Proposed by S. Pit Corder and Larry Selinker, the concept of interlanguage was established as learners\u0027 independent system of the second language, which is of neither the native language nor the second language, but a continuum or approximation from one extreme of his native language to the other of the second language. Among the three characteristics-systematicity, permeability and fossilization-of interlanguage, fossilization is defined as a process occurring from time to time in which incorrect linguistic features become a permanent part of the way a person speaks or writes a language.Key: It refers to the type of language constructed by second or foreign language learners who are still in the process of learning a language. It’s a language system between the target language and the learner’s native language, and imperfect compared with the target language, but not mere translation from the learner’s native language. For example, when the Chinese student is learning English, he may make errors like “to touch the society”.