Stabilized interlanguage patterns and fossilization risks in Indonesian EFL academic writing: A qualitative error analysis

Abstract

Stabilized interlanguage remains a persistent concern in second language acquisition, particularly in the academic writing of English as a Foreign Language (EFL) learners who have received years of formal instruction. Although interlanguage stabilization has been widely discussed in SLA scholarship, less attention has been given to how it appears in the academic writing of advanced Indonesian EFL learners. This study addresses this gap by examining recurrent lexico-syntactic, grammatical, and discourse-level errors that may indicate stabilized interlanguage patterns and fossilization risks. Using a qualitative descriptive design, the study involved seven undergraduate EFL learners from an Indonesian university who were selected purposively based on their experience in academic essay writing. Data were collected through controlled argumentative writing tasks and analyzed using error analysis supported by thematic coding. The findings show recurring problems in article use, prepositional choice, cohesion devices, nominalization, verb form, collocation, and academic register. These patterns suggest that some learners were able to communicate their intended meanings, yet still relied on non-target-like forms that had become familiar in their writing. The study also indicates that such patterns may be shaped by first-language transfer, limited noticing, insufficient corrective feedback, and repeated use of communicatively acceptable expressions. The findings highlight the need for discourse-level feedback, genre-based instruction, and targeted pedagogical support that helps learners notice, revise, and move beyond stabilized patterns. This study contributes to SLA and EFL writing research by situating fossilization risks within Indonesian higher education academic writing in university contexts.