In the literature of SLA the two issues have drawn the most attention of researchers on how interlanguage of L2 develops and what the endstate the L2 learner reaches looks like. This study also tries to show how the inter- languages of Korean learners of English at different proficiency levels work with most error stricken forms from six English textbooks currently adopted in Korea. To do so, four groups of Korean students at different proficiency levels were tested with those error prone forms. And the results confirm that their acquisitions are not sequentially consistent and is not congruous with each other. In addition, this study found that there were 11 expressions all groups missed. All these confirmations mean that the 11 forms may be candidates for fossil- ization for Korean English learners. Furthermore, as learning proceeds, their interlanguage structures become quite different, especially when error types are considered. This shows how Korean learners interlanguage structures change as proficiency level gets higher.
1. Introduction
2. Literature Review
3. The Study
4. Discussion
5. Conclusion