Tahmineh Khalili - Ph.D. Student of Applied Linguistics, Department of English, University of Isfahan
Dariush Nejad Ansari Mahabadi - Assistant Professor of Applied Linguistics, Department of English, University of Isfahan

Regarding the remarkable increase in multilingualism expansion and research, this study aimed to focus on the case of Iranian multilingual learners in terms of the cognitively default language used for word choice in L۴ writing task when the instruction is in L۱. This study also tried to account the issues via the theories notified by the Parasitic Model (PM). The main concentration in this research was on learners’ L۴ writing analysis through considerations on the learners’ diaries and reports on semi-structured interviews. The results showed that the cases under investigation utilized various strategies both in isolation and in combination with other strategies which could also provide justifications for the operationalization of PM in word choice in L۴ writing tasks. The findings of this study might be beneficial for the development of successful multilingual learners in addition, teachers, curriculum designers, teacher training designers, and materials developers may benefit from the results of this study to teach multilingual learners in a more efficient way. Another implication of this study might be a call for more consideration about the increasing multilingual learners for both pedagogical and research purposes.

L۴ writing, Parasitic Model, Vocabulary learning, Word choice, Writing task.