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The aim of the present study was to examine whether Metacognitive Intervention (MI) in their first language (L۱) had any significant effect on English as a Foreign Language (EFL) learners’ Working Memory (WM) in listening comprehension when they received it. In addition, it measured whether gender had any effect on EFL learners’ listening comprehension when they receive MI through L۱. To this end, ۶۰ Iranian EFL learners were selected through a Quick Placement Test and were assigned into two male and female experimental groups. These experimental groups received an eight-week intervention program, designed by the pedagogical cycle proposed by Goh and Vandergrift (۲۰۲۲). After the metacognitive intervention in L۱, two posttests including a working memory capacity test and a listening comprehension test were administered. The findings indicated that there was a significant effect on EFL learners’ working memory in listening comprehension after they received MI in L۱. It was also found that gender had a significant effect on the EFL learners’ working memory and listening comprehension when they receive MI in L۱. The findings might contribute to assisting language instructors to adopt strategy-based approaches to teaching listening. Furthermore, curriculum designers and ELT policymakers might consider metacognitive intervention as an effective teaching approach and add it to EFL learners’ curriculum.

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Knowing how to think about the language learning process is conducive to effective learning especially in the case of grammar structures. Metacognition, a concept derived from cognitive psychology, can assist learners in this case. With regard to young adolescents at lower proficiency levels, there is a long-standing debate on whether to use L۱ for teaching metacognitive strategies since learners might not be efficient enough in terms of understanding the concept of metacognition. Therefore, this small-scale experimental study focused on the effect of grammar instruction through the metacognitive intervention delivered in L۱ on the EFL pre-intermediate learners' grammatical performance in English and investigated their attitudes towards grammar instruction delivered in L۱. To fulfill these purposes, a homogenous group of ۲۰ language learners was randomly divided into an experimental group (n =۱۰), which received grammar instruction through the metacognitive intervention delivered in L۱, and a control group (n =۱۰), which received the instruction only in English without grammar instruction through the metacognitive intervention delivered in L۱. The results of the independent samples t-test indicated that the experimental group did not outperform the control group in terms of all four English grammar points, namely present perfect, simple past tense, comparative and superlative adjectives, and past progressive. In addition, the findings obtained from the five-point Likert scale questionnaire which was distributed among the learners suggested that they had positive attitudes towards the use of L۱ (Persian) in teaching English grammar. We argue that low working memory capacity, overreliance on translation, and less-cognitively activated L۲ processes may account for the low performance of the experimental group learners in the grammar tests. The implication is that the L۱ use in an L۲ classroom can be helpful in teaching L۲ grammar through the metacognitive intervention, but future studies need to examine how and to what extent L۱ should be used to yield more effective results in the case of lower-proficiency learners in an EFL context.
 

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سامانه‌های کنترل به‌وسیله جت جانبی به‌عنوان یک جایگزین موردپسند برای سامانه‌های کنترل متعارف در سال‌های اخیر موردتوجه قرارگرفته‌اند. در تحقیق حاضر که به دو بخش تقسیم می‌شود اثرات اندرکنش جت جانبی و جریان مستقیم مافوق‌صوت روی رفتار آیرودینامیکی یک پرتابه استاندارد در زاویه حمله صفر درجه مورد مطالعه قرار گرفته است. در بخش اول نتایج حاصل از بررسی تاثیر پارامترهایی نظیر مکان جت، عدد ماخ و نوع نازل به‌کاررفته روی ضریب فشار، ضریب و نیروی پسا و نحوه توزیع فشار روی بالک‌ها ارایه شده و مورد تحلیل قرار گرفته‌اند. در بخش دوم ضرایب پایداری طولی استاتیکی و دینامیکی پرتابه در حضور جت جانبی به‌دست آمده و با توجه به پارامترهای ذکر شده ارزیابی شده‌اند. با توجه به نتایج، مکان جت موثرترین پارامتر محسوب می‌شود. در بخش اول نحوه توزیع فشار روی بالک‌ها وابستگی بسیار زیادی به مکان جت دارد. تاثیر عدد ماخ به روی ضریب فشار و نیرو و ضریب پسا نیز قابل‌توجه است. همچنین تغییر توزیع فشار روی بالک‌ها با تغییر عدد ماخ در مکان‌های انتهایی بیشتر به چشم می‌آید. در بخش دوم تاثیر حضور جت جانبی باعث کاهش پایداری طولی استاتیکی می‌شود. همچنین افزایش عدد ماخ باعث کاهش پایداری طولی دینامیکی شده و تغییر مکان جت رفتاری غیرخطی روی اندازه ضریب میرایی گشتاور پیچشی ایجاد می‌کند، در نتیجه انتخاب مکان مناسب جت به پارامترهایی که مدنظر طراح است بستگی دارد. با توجه به نتایج به‌دست‌آمده تاثیر نوع نازل بر تمام موارد موردبررسی ناچیز بوده است.

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