Humanitatis: Journal of Language and Literature SK Dirjen DIKTI Nomor 36/E/KPT/2019 Vol. No. December 2025, pp. ISSN (Prin. : 2338-9362 ISSN (Onlin. : 2477-2267 English Language Acquisition through Parliamentary Debating: A Case Study at Politeknik Kesehatan Mataram Erwin Suhendra*1 . Wahyu Kamil Syarifaturrahman1 . Lalu Arwan Darmajaya2 1 Universitas Bumigora. Mataram. Indonesia 2 Politeknik Kesehatan Kemenkes. Mataram. Indonesia Received: 19th September 2025 | Revised: 17th December 2025 | Accepted: 18th December 2025 * Corresponding author. E-mail: erwin@universitasbumigora. Abstract British Parliamentary (BP) debate is widely adopted in EFL/ESP classrooms, but prior studies often report score gains without explaining how debate drives language development. This study aimed to trace the mechanisms by which BP debate fosters L2 acquisition, focusing on fluency, discourse organisation, and pragmatic competence. Using a qualitative research method with process tracing, eight medical ESP students at Politeknik Kesehatan Mataram completed four full BP rounds. Multimodal data included audioAevideo recordings of speeches and POIs, written texts from case building, observational notes, and reflective journals/interviews. Data were transcribed and analysed through reflexive thematic analysis guided by three constructs: noticing, modified output, and Results show a consistent inputAeprocessingAeoutputAemediation cycle: self-repairs declined while lexical precision increased. signposting and connectors became denser and more strategic. POIs/rebuttals featured clearer negotiation through hedging, uptake, and reformulation. and adjudicator feedback catalysed planned changes in subsequent rounds, indicating developing self-regulation. Overall. BP debate functions as a rich, mechanism-rich environment that integrates sociocultural mediation with interactionist learning, transforming performance from mechanical repetition to purposeful, confident communication. These findings support using BP debate as an authentic task-based pedagogy for ESP learners. Keywords: British Parliamentary Debat. Language Fluency. Pragmatic Competence. Second Language Acquisition. Sociocultural Mediation. Task-Based Learning. How to Cite: Suhendra. Syarifaturrahman. , & Darmajaya. English Language Acquisition through Parliamentary Debating: A Case Study at Politeknik Kesehatan Mataram. Humanitatis : Journal of Language and Literature, 12. , 87-100. Copyright A2025 The Authors. This article is published by Universitas Bumigora under the CC BY-SA license. INTRODUCTION Language learning is a complex cognitive and social process that involves continuous interaction, negotiation of meaning, and feedback. In recent years. British Parliamentary (BP) debate has gained increasing attention as a pedagogical tool in English as a Foreign Language (EFL) and English for Specific Purposes (ESP) contexts. The structure of the BP debateAiwith four teams, eight speakers, and timed speechesAicreates a natural linguistic environment in which learners must simultaneously engage in reading, listening, speaking, and writing. Online at https://journal. id/index. php/humanitatis/ D OI: 10. 30812/humanitatis. Humanitatis: Journal of Language and Literature SK Dirjen DIKTI Nomor 36/E/KPT/2019 Vol. No. December 2025, pp. ISSN (Prin. : 2338-9362 ISSN (Onlin. : 2477-2267 emphasized by Sukino et al. BP debate provides an authentic framework for developing communicative competence by integrating argumentation, persuasion, and pragmatic adaptation. Through debate, learners are exposed to dynamic language use that promotes both fluency and accuracy in real-time communication. Previous research underscores the multifaceted benefits of debate pedagogy in language education. Studies such as those by Majidi et al. and Guo et al. demonstrate that structured debate enhances fluency, coherence, and pragmatic control. Likewise. -C. Lin . found that argumentation-based inquiry fosters studentsAo willingness to communicate, while Mesa et al. observed improvements in studentsAo critical thinking and organizational abilities. Debate-based instruction also contributes to the development of argumentative writing and rhetorical skills (Majidi et al. , 2. However, much of this literature tends to measure outcomes quantitativelyAiimproved scores or proficiency ratingsAiwithout sufficiently exploring the processes underlying such growth. This study addresses that gap by adopting a mechanism-based perspective that focuses on how BP debate facilitates language learning. Theoretically, it draws from sociocultural and interactionist frameworks, which emphasize that language acquisition occurs through socially mediated interactions and meaningful communicative exchanges (Lantolf & Poehner, 2. In BP debate, learners co-construct knowledge by responding to opponentsAo arguments, engaging in Points of Information (POI. , and receiving adjudicator feedbackAiall of which mirror the dialogic processes central to these theories. Moreover, the study aligns with Task-Based Language Teaching (TBLT), wherein debate functions as a goal-oriented communicative task that stimulates output, negotiation, and noticing (Schwalbach, 2023. Slapin & Proksch, 2. The novelty of this research lies in tracing how language learning occurs during debate activities rather than merely proving that it does. By examining linguistic behavioursAisuch as self-repair, use of signposting, and the adoption of cohesive connectorsAithe study identifies specific mechanisms for improving fluency and organization. It also investigates how feedback mediation supports uptake and long-term development. This process-oriented approach allows for a deeper understanding of the pedagogical impact of debate, particularly in the ESP setting of medical students at Politeknik Kesehatan Mataram. In practical terms, this studyAos significance extends beyond debate as a competitive event. It demonstrates how BP debate can serve as a replicable model for communicative instruction in higher education, especially in professional domains requiring analytical discourse. By mapping out the linguistic and cognitive mechanisms of debate-based learning, the study aims to inform curriculum design, teacher training, and assessment practices. Ultimately, it contributes to a growing body of work that reframes debate not only as a means of expression but also as a process of acquisition, aligning interactional engagement with sustained language development. RESEARCH METHOD This study used a qualitative method employing a process-tracing design to understand how British Parliamentary (BP) debate facilitates second-language (L. acquisition among English for Specific Purposes (ESP) Process tracing is a systematic examination of diagnostic pieces of evidence as part of a temporal sequence of events which is observed throughout each step of the analytical timeline, focusing on the order and interactions of events (Andersen et al. , 2022. Collier, 2011. Schwartz, 2016. Simister & Scholz, 2. Process tracing is used to identify, order, and explain the links between debate activities . nput, case building, delivery, feedbac. and observed linguistic, cognitive, and affective changes across repeated rounds (Ariaans & Reibling, 2024. Inya, 2025. Mykkynen et al. , 2024. Syvytery et al. , 2023. Truan, 2021. Yazdanmehr et al. , 2. It was selected because it can identify and describe how learnersAo linguistic behaviours evolve during debate activities, rather than measuring proficiency through standardized testing. Process tracing captures the sequence of language use, interaction, and This study provides a framework to trace how specific debate phases . nput, case building, delivery, and feedbac. produce observable linguistic and cognitive changes. Online at https://journal. id/index. php/humanitatis/ D OI: 10. 30812/humanitatis. Humanitatis: Journal of Language and Literature SK Dirjen DIKTI Nomor 36/E/KPT/2019 Vol. No. December 2025, pp. ISSN (Prin. : 2338-9362 ISSN (Onlin. : 2477-2267 Research Site and Participants The study was conducted in the spring term of the academic year 2024/2025 at Politeknik Kesehatan Mataram (Poltekkes Matara. in an extracurricular English for Specific Purposes (ESP) class where British Parliamentary (BP) debate is formally integrated. Participants were eight tertiary-level medical students (N = . , organized into four BP teams . wo debaters per tea. They represented three programs. Medical Laboratory Techniques (MLT. n = . Nursing . = . , and Midwifery . = . and their semesters are: seventh semester . = 2. both MLT), fifth semester . = 3. two MLT, one Nursin. , and third semester . = 3. two MLT, one Midwifer. Purposive sampling was applied for three reasons: . the students are ESP learners who routinely engage in analytic, discipline specific English, making debate a relevant communicative task. they demonstrated intermediate English proficiency with prior classroom exposure to BP debate, ensuring meaningful participation while leaving scope for development. they belonged to the same English group program and were taught by the same instructor, providing a homogeneous instructional context for process tracing. All students provided informed consent. pseudonyms are used in reporting. Data Collection The study utilized multimodal triangulation, combining four primary data sources to ensure validity and richness of interpretation (Chaparro-Moreno et al. , 2019. Garcia & Schleppegrell, 2021. Perry et al. , 2018. Sari & Abrar, 2024. Sirine et al. , 2020. Wandani et al. , 2. Table 1. Multimodal Triangulation Data Source AudioAevideo recordings Written artifacts Observational notes Reflective journals and interviews Purpose Capture real-time interactions and linguistic behaviours Examine planning, structuring, and reflection processes Provide contextual data and field insights Explore self-reported noticing and uptake Examples Debate rounds. POIs, rebuttals Motion analysis sheets, case drafts, reply notes Researcher field logs on timing, discourse flow Post-debate reflections and semistructured interviews Table 1 summarises each source, its analytic purpose, and concrete examples: AudioAevideo recordings documented real time interactional moves . ubstantive speeches. POIs, rebuttal. and were the primary evidence for fluency markers . auses, hesitations, self repair. and discourse devices . ignposting, connector. Written texts . otion analysis sheets, case drafts, reply note. revealed planning, organisation, and the development of argumentative structure prior to delivery. Observational notes supplied contextual detail on timing, floor management, and discourse flow, supporting interpretation of the recordings. Reflective journals and interviews captured learnersAo noticing and perceived uptake. these texts were cross checked against behavioural evidence in recordings to corroborate self reports. The multimodal data enabled both textual and visual analysis, enhancing validity through cross-modal consistency. Research Procedures Phase 1: Debate Preparation (Input & Processin. Learners received the motion 35 minutes before each round. They engaged in group discussion, developing logical cases and identifying keywords. This phase was coded as Auinput processing,Ay focusing on lexical searches and conceptual framing. Phase 2: Debate Delivery (Outpu. Each participant delivered a 7-minute speech interspersed with 15-second Points of Information (POI. Speech recordings were analyzed for linguistic complexity, fluency markers . auses, hesitations, self-repai. , and cohesion devices . ignposting, connector. Online at https://journal. id/index. php/humanitatis/ D OI: 10. 30812/humanitatis. Humanitatis: Journal of Language and Literature SK Dirjen DIKTI Nomor 36/E/KPT/2019 Vol. No. December 2025, pp. ISSN (Prin. : 2338-9362 ISSN (Onlin. : 2477-2267 Phase 3: Adjudication and Feedback (Mediatio. Judges and coaches provided feedback following each round. Feedback content was categorized under language accuracy, organization, and argument clarity. This mediation phase was essential for tracing learning uptake across rounds. Figure 1. Data Collection Cycle Figure 1 visualises this loop beginning at debate preparation, proceeding to debate delivery, and moving into adjudication and feedback. The circular arrows indicate that feedback from a given round functions as input for the next motion, thereby operationalising the studyAos mechanism focus: repeated opportunities for noticing, modified output, and mediated development. This iterative cycle captures the dynamic interplay between task performance and mediated learning. Data Analysis The analysis employed reflexive thematic analysis (Braun & Clarke, 2. combined with mechanism Three analytical constructs guided data interpretation: - Noticing Ae learner awareness of linguistic form or meaning gaps, observed through verbal cues and reflective journals (Arif & Naeem, 2. - Modified Output Ae linguistic adjustments following feedback or peer challenge, evident in POI responses and speech revisions (Komoder et al. , 2. - Mediation Ae guided learning moments, particularly feedback interactions that promote uptake (Leaver & Srdarov. Twenge, 2. Table 2. Multimodal Triangulation Mechanism Noticing Modified Output Mediation Operational Definition Recognition of linguistic gap Reformulation after feedback Peer or coach scaffolding Example Evidence AuOh. I should use equity instead of equality. Ay AuRegulate. I mean restrict. Ay Judge feedback prompting clearer definitions All recordings were transcribed verbatim. Analysis combined reflexive thematic analysis with mechanismoriented process tracing. Three a priori analytic constructs guided coding: Noticing Ai moments where learners identify form/meaning gaps . , explicit self-correction or metalinguistic comments in journal. Modified Output Ai reformulations attributable to interactional pressure or feedback . , term replacement during POIs. precise wording in later round. Mediation Ai teacher/peer/adjudicator scaffolding supporting appropriation of new forms/strategies. Online at https://journal. id/index. php/humanitatis/ D OI: 10. 30812/humanitatis. Humanitatis: Journal of Language and Literature SK Dirjen DIKTI Nomor 36/E/KPT/2019 Vol. No. December 2025, pp. ISSN (Prin. : 2338-9362 ISSN (Onlin. : 2477-2267 Table 2 operationalises each construct with definitions and in data exemplars . Auequality Ie equityAy replacement following adjudicator commen. The table functions as a codebook snapshot, clarifying how abstract constructs map onto observable indicators. Two independent coders piloted the framework on a subset of data, discussed discrepancies, and refined Inter-rater reliability achieved 85% agreement before full coding. Coded segments were clustered into themes . luency development, organisational growth, pragmatic contro. and then ordered chronologically to link change to specific phases/events, as evidenced in Figure 1. Data were analyzed iteratively, with codes refined through cross-checking among two independent coders to ensure inter-rater reliability . %). Member checks with participants validated interpretive accuracy. Validity and Ethical Considerations To ensure credibility and trustworthiness, the study employed multiple validation procedures: - Triangulation: Cross-verification of findings through multimodal data (Gilfoyle et al. , 2024. OchiengAo OngAoondo & Borg, 2011. Sholeh et al. , 2. - Reflexivity: Maintenance of researcher logs to document biases and interpretive stance (Gunawan, 2015. Lietz et al. , 2. - Member Checking: Participant review of findings for accuracy (Komoder et al. , 2023. Mackie et al. , 2024. Spies et al. , 2. - Peer Debriefing: External review of data interpretation (Khoza-Shangase & Sebothoma, 2022. Lawal et al. Ethical safeguards included informed consent, confidentiality, and separation of researcher and instructor roles. Research materials were anonymized, and only aggregate results were published. Research Contextualization This methodological framework aligns with the sociocultural theory of L2 learning, where mediation and social interaction act as catalysts for development (Lantolf & Poehner, 2. It also reflects task-based learning principles, as debate functions as an authentic communicative task requiring goal-oriented use of language (Schwalbach, 2023. Slapin & Proksch, 2. By combining these theoretical orientations with empirical tracing, the study provides a holistic view of how debate supports linguistic, cognitive, and affective growth. FINDINGS AND DISCUSSION Overview of Debate-Based Learning Cycle The implementation of British Parliamentary (BP) debate as a pedagogical strategy revealed a consistent inputAeprocessingAeoutputAemediation cycle that facilitated learnersAo linguistic, cognitive, and affective development. The cycle illustrated in Figure 2 shows the sequential relationships among exposure, language production, and reflective learning. Across four debate rounds, participants exhibited measurable improvements in fluency, coherence, and pragmatic awareness, confirming the dynamic nature of debate as a learning ecology (Schwalbach, 2023. Slapin & Proksch, 2. Figure 2. InputAeProcessingAeOutputAeMediation Cycle Online at https://journal. id/index. php/humanitatis/ D OI: 10. 30812/humanitatis. Humanitatis: Journal of Language and Literature SK Dirjen DIKTI Nomor 36/E/KPT/2019 Vol. No. December 2025, pp. ISSN (Prin. : 2338-9362 ISSN (Onlin. : 2477-2267 Figure 2 visualises how each debate round unfolds as a repeated sequence that enables learning to accumulate across time. The cycle starts with Motion Reading, which primes topical knowledge and sets the task goal. progresses to Case Building, where students collaboratively frame claims and supporting reasons. moves to Delivery & POIs, where arguments are articulated and challenged in real time. and concludes with Feedback & Reflection, where adjudicator comments and self-appraisals consolidate learning. The horizontal arrow labelled Uptake & Modified Output underlines that feedback does not terminate the process. rather, it loops forward and becomes the input for the next motion. In analytic terms, the figure operationalises the studyAos mechanism focus: repeated opportunities for noticing, modifying output, and mediated development that together drive observable changes in fluency, organisation, and pragmatic control across four rounds. This iterative structure provided recurrent opportunities for linguistic noticing, adaptation, and performance improvement, demonstrating the interdependence of interaction and mediation. Fluency Development and Self-Repair A central indicator of linguistic growth was the decreasing frequency of self-repair across rounds. In early sessions, learners frequently paused, reformulated, or replaced lexical items. however, later sessions revealed more efficient retrieval and reduced hesitation (Adewumi & Adewumi, 2025. Fitzpatrick & Thwaites, 2020. Huang et al. Kouhia, 2. Table 3 summarizes the progression in self-repair behaviors. Table 3. Frequency of Self-Repair Across Debate Rounds Round Average Repairs per Speech Example Interpretation AuThey are responsibleAiuh. I mean accountable for. Ay AuWe must prohibitAino, regulate digital markets. Ay AuGovernment has powerAior rather, coordination value. Ay AuThis ensures equalityAiequity in access models. Ay Early fluency monitoring Awareness of precision Conceptual refinement Mature lexical control A primary indicator of fluency growth was the declining frequency of self-repairs. As shown in Table 3, average repairs per speech decreased from 8 (Round . to 3 (Round . Early utterances contained hesitation and lexical searching . , responsibleAiuhAiaccountabl. , signalling fragile retrieval. By Round 3, repairs increasingly reflected conceptual refinement rather than breakdown . , powerAicoordination valu. , and by Round 4, learners demonstrated mature lexical control . , equality Ie equit. Interpreted through the Output Hypothesis, sustained pressure to communicate during speeches and POIs appears to have promoted automatization and restructuring of interlanguage, reducing the need for overt repair while increasing precision. This pattern aligns with the Output Hypothesis (Castro, 2005. Sodiqova, 2. , suggesting that the need to communicate effectively under pressure stimulates restructuring of interlanguage and automatization of linguistic routines. Organizational Growth through Signposting and Connectors ParticipantsAo speeches demonstrated increasing sophistication in signposting and use of connectors, reflecting enhanced coherence and argument organization. Initially, transitions relied on simple conjunctions. over time, learners incorporated complex markers . Auin contrast,Ay Auas a result,Ay AuthereforeA. , enabling logical argument progression (Crible & Degand, 2019. Dumlao & Wilang, 2019. -L. Lin et al. , 2. Table 4 presents the observed Table 4. Development of Signposting and Connectors Round Average Signposts per Speech Common Connectors Observation and, so, but because, however therefore, on the other hand Disconnected statements Improved transitions Structured flow Online at https://journal. id/index. php/humanitatis/ D OI: 10. 30812/humanitatis. Humanitatis: Journal of Language and Literature SK Dirjen DIKTI Nomor 36/E/KPT/2019 Vol. No. December 2025, pp. Round Average Signposts per Speech ISSN (Prin. : 2338-9362 ISSN (Onlin. : 2477-2267 Common Connectors Observation consequently, in contrast Persuasive coherence Table 4 shows steady gains in discourse organisation. Average signposts per speech rose from 3 to 14 across rounds, with a qualitative shift from simple coordination . nd, so, bu. to logical relational markers . herefore, on the other hand, consequently, in contras. These markers improved top down guidance for listeners . previewAepointAetransitio. and local cohesion between propositions. Observational notes and adjudicator sheets indicated that clearer signposting was consistently associated with higher speaker rankings, suggesting that repeated exposure to BP genre conventions strengthened studentsAo rhetorical schemata and planning. The steady increase in structural markers enhanced argument clarity and contributed to higher adjudicator scores, confirming that linguistic organization improves through repeated engagement with genre conventions. Pragmatic Control and Meaning Negotiation through POIs and Rebuttals Points of Information (POI. and rebuttals emerged as pivotal for pragmatic fluency. Early interactions were hesitant and defensive. later, participants demonstrated refined discourse strategiesAiacknowledging opposing views, reformulating responses, and employing politeness markers (Ren & Cui, 2025. Tsunemoto & Trofimovich. Table 5 illustrates typical instances of meaning negotiation. Table 5. Examples of Meaning Negotiation in POIs Debate Round Scenario Clarifying Aueconomic protectionAy Reframing counter-models Softening disagreement Incorporating opponentAos term Linguistic Strategy Lexical substitution Modified output Hedging Uptake Pragmatic Function Promotes understanding Adapts communication Maintains rapport Builds dialogue coherence Table 5 traces a progression from early lexical substitution for clarity (Round . to strategic modified output (Round . , increased use of hedging to manage face and stance (Round . , and final round uptake of opponent terminology to build dialogue coherence (Round . These moves show learners learning to balance assertiveness and accommodation, a hallmark of pragmatic competence. The evidence corroborates interactionist claims that negotiation of meaningAiespecially under time pressureAipushes learners to test hypotheses about formAemeaning mappings and discourse expectations. These findings align with interactionist principles (Long, 2. , where negotiation of meaning drives comprehension and acquisition through communicative repair. Genre Familiarization and Argument Clarity Repeated exposure to the BP genre reinforced learnersAo mastery of discourse organization and logical As learners internalized the claimAereasonAeimpact structure, their arguments transitioned from fragmented assertions to well-linked analytical reasoning (Karsan et al. , 2017. Li et al. , 2025. Scott, 2. Table 6 demonstrates this evolution. Table 6. Development of Argument Clarity Debate Round Scenario Clarifying Aueconomic protectionAy Reframing counter-models Softening disagreement Incorporating opponentAos term Linguistic Strategy Lexical substitution Modified output Hedging Uptake Pragmatic Function Promotes understanding Adapts communication Maintains rapport Builds dialogue coherence Table 6 documents a shift from loose causeAeeffect assertions to conditional logic, then to explicit claimAe reasonAeimpact statements, and finally to comparative evaluation that weighs models and trade offs. Artefacts from Online at https://journal. id/index. php/humanitatis/ D OI: 10. 30812/humanitatis. Humanitatis: Journal of Language and Literature SK Dirjen DIKTI Nomor 36/E/KPT/2019 Vol. No. December 2025, pp. ISSN (Prin. : 2338-9362 ISSN (Onlin. : 2477-2267 case building sheets show that by Rounds 3Ae4, teams intentionally planned impact calculus . , scope, magnitude, probabilit. and embedded it into their speech summaries. This pattern indicates that the genre provided a task based scaffold for higher order reasoning, not merely surface level language practice. These results indicate that debate functions as a task-based scaffold promoting cohesion, analytical reasoning, and rhetorical awareness. Feedback Mediation and Uptake Patterns Feedback was instrumental in facilitating learning uptake and longitudinal development. Adjudicator comments on lexical precision, delivery pace, and coherence led to observable improvement in subsequent performances (Parrish et al. , 2021. Thomson, 2021. Wambsganss et al. , 2. LearnersAo reflective journals confirmed active internalization of feedback, supporting sociocultural perspectives that view mediation as central to learning (Lantolf & Poehner, 2. Table 7 highlights examples of feedback-based progress. Table 7. Development of Argument Clarity Feedback Focus Vocabulary Organization Delivery Example of Feedback AuAvoid vague terms like Aothing. AoAy AuSummarize before next point. Ay AuLower speed. emphasize contrasts. Ay Observable Change Use of domain-specific terminology Clearer transitions and summaries Controlled tone and rhythm Interpretation Enhanced precision Improved cohesion Better persuasion Table 7 maps typical comments to subsequent observable changes. For example, lexical feedback (Auavoid vague termsA. preceded consistent adoption of domain specific terminology in later rounds. organisational feedback (Ausummarise before next pointA. was followed by clearer macro signposting and concise round ups. feedback (Auslow down. emphasise contrastsA. yielded improved prosodic control and contrastive emphasis in extensions and summaries. Reflective journals confirmed that students noticed these points and planned explicit changes, which were then visible as modified output in the next iterationAievidence of mediation leading to self Through sustained mediation, learners gradually achieved self-regulated communication, resonating with VygotskyAos . Zone of Proximal Development (ZPD) concept (Infante & Poehner, 2019. Soozandehfar et al. , 2. The findings substantiate the alignment between BP debate pedagogy and socioculturalAeinteractionist models. Debate fosters social interaction and co-construction of meaning, fulfilling Vygotskyan principles of mediated Simultaneously, the iterative structure of output and feedback validates interactionist assumptions about input modification and output restructuring. These mechanisms confirm that debate serves as an experiential laboratory for applied SLA theory (Yyzly & Atay, 2. The findings of this study support and extend prior research in several important ways. Consistent with previous works such as Majidi et al. Majidi et al. , and Guo et al. -C. Lin . , the present study confirms that British Parliamentary (BP) debate enhances fluency, coherence, and pragmatic competence in second language acquisition. However, it differs from much of the existing literature by providing a detailed, mechanism-based account of how such development unfolds. Instead of relying solely on quantitative proficiency measures, this study employs a descriptive-qualitative approach using process tracing, enabling the identification of specific learning mechanismsAinamely noticing, modified output, and mediationAias theorized by Arif and Naeem . Komoder et al. , and Lantolf and Poehner . These mechanisms are evidenced through declining self-repair frequencies (Fitzpatrick & Thwaites, 2020. Kouhia, 2. , improved use of discourse markers (Crible & Degand, 2019. Dumlao & Wilang, 2. and enhanced pragmatic negotiation in POIs (Ren & Cui, 2025. Tsunemoto & Trofimovich, 2. Furthermore, while Mesa et al. and Scott . highlighted the critical thinking and argument clarity developed through debate, this study goes further by documenting how learners internalize genre-specific rhetorical structures over multiple rounds of debate. The integration of feedback (Parrish et al. , 2021. Wambsganss et al. , 2. as a mediating factor in the development of self-regulation and strategic communication also aligns with sociocultural perspectives. In doing so, this research not only supports but also enriches the ongoing Online at https://journal. id/index. php/humanitatis/ D OI: 10. 30812/humanitatis. Humanitatis: Journal of Language and Literature SK Dirjen DIKTI Nomor 36/E/KPT/2019 Vol. No. December 2025, pp. ISSN (Prin. : 2338-9362 ISSN (Onlin. : 2477-2267 conversation in debate-based SLA research by illustrating how language acquisition occurs dynamically through the inputAeprocessingAeoutputAemediation cycle. Therefore, it contributes a theoretically grounded and empirically rich account of BP debate as a replicable, mechanism-rich learning environment in ESP contexts. CONCLUSION This study shows that British Parliamentary (BP) debate operates as a dynamic, mechanism-based environment for L2 development in EFL/ESP contexts. Across four rounds, the iterative inputAeprocessingAeoutputAemediation cycle yielded measurable gains: fluency improved as self-repairs declined. organisational coherence strengthened through denser, more strategic signposting. and pragmatic competence advanced via effective negotiation in POIs and targeted rebuttals. Feedback served as a mediator, triggering uptake and modifying output, enhancing lexical precision, delivery control, and argument clarity. Future research should examine the durability and transferability of these gains through longitudinal tracking and cross-institutional replications, ideally combining qualitative process tracing with selective quantitative indicators . , repair rates, discourse marker densit. Comparative studies across proficiency bands and disciplinary ESP domains can test boundary conditions, while design experiments can vary feedback timing. POI intensity, or scaffolding to isolate high-leverage mechanisms. Investigations of metacognitive growth . , planning, monitoring, evaluatio. and affective factors . , anxiety reductio. would extend the mechanism account and guide scalable implementations of BP debate in higher education. REFERENCES