發音是影響有效口語溝通的重要因素。此外，清晰易懂的發音是溝通能力的關鍵。近十年來，關於發音的研究顯著增多，涵蓋了印尼學生在輔音和元音發音方面的困難。然而，關於影響言語清晰度的因素的研究仍然有限。本研究的主要目的是探討印尼大學生英語言語清晰度的變量，以及印尼大學生在英語言語產出過程中影響英語言語清晰度的變數。本研究收集了110名印尼學生作為說話者的英語程度和聽力理解測驗、問卷調查、詞彙測驗和句子測驗（使用TOCS+清晰度軟體應用程式）的資料。這些測驗由270名以英語為母語的聽眾使用封閉式任務進行評判，並由另外270名以英語為母語的聽眾使用開放式任務進行評判。使用 IBM SPSS 統計軟體 23 版透過多元線性迴歸、皮爾森相關、點二列相關、混合變異數分析和描述性統計分析了收集的數據。分析表明，聽力理解、英語學習時間和日常英語使用顯著預測了語音清晰度。輔音方式和元音前後對語音清晰度的影響更大。性別、自我評價和對英語的態度等變數並未顯示出顯著的影響。迴歸模型顯示出強大的預測能力（單字的 R² = 0.581；句子的 R² = 0.469）。實際意義強調在英語課程中整合有針對性的語音訓練、使用科技輔助發音工具和強化聽力活動，以提高清晰度。限制包括樣本代表性和範圍僅限於清晰度而沒有考慮社會接受度或聽眾多樣性。未來的研究應擴大參與者的人口統計範圍，納入縱向研究設計，並探索超音段特徵和社會文化背景，以進一步豐富對印尼英語語音清晰度的理解。本研究結果可望為英語教育工作者提供有益的見解，幫助他們制定教學策略，以應對印尼大學生面臨的發音難題。

Pronunciation is an essential factor that significantly influences oral communication effectively. Moreover, having a clear and understandable pronunciation is a crucial aspect of being competent in communicating. In the last decade, research on pronunciation has markedly increased, encompassing difficulties in both consonants and vowels produced by Indonesian students. However, research on the factors contributing to speech intelligibility was still limited. The primary aim of this research was to explore the variables from Indonesian college students which contribute to their English speech intelligibility and the variables in English speech production of Indonesian college students which contribute to English speech intelligibility. The study generated data from English proficiency and listening comprehension tests, questionnaires, word tests and sentence tests (by using TOCS+ intelligibility software application), which were produced by 110 Indonesian students acting as speakers. These tests were judged using closed-set tasks by 270 native listener speakers, and open-set tasks by another 270 native listener speakers. The data collected was analyzed by using IBM SPSS statistics version 23 through multiple linear regression, Pearson correlation, point-biserial correlation, mixed ANOVA, and descriptive statistics. The analysis revealed listening comprehension, length of English learning, and daily English use significantly predicted speech intelligibility. Consonant manner and vowel front-back have a greater impact on speech intelligibility. Variables such as gender, self-evaluation, and attitude toward English showed no significant effect. The regression models demonstrated substantial predictive power (R² = 0.581 for words; 0.469 for sentences). Practical implications emphasize the integration of targeted phonetic training, use of technology-assisted pronunciation tools, and enhanced listening activities in English curricula to improve intelligibility. Limitations include sample representativeness and the scope confined to intelligibility without considering social acceptability or listener diversity. Future research should expand participant demographics, incorporate longitudinal designs, and explore supra-segmental features and socio-cultural contexts to further enrich understanding of Indonesian English speech intelligibility. The study's findings have the potential to offer useful insights to English educators looking to develop teaching strategies to tackle the pronunciation difficulties faced by college students in Indonesia.

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