本研究旨在了解台灣大學生如何應用校內可及資源－國際演講協會分會，來發展自主學習與加強英語能力。本研究以情境學習理論(Situated Learning Theory)為基礎，採用民族誌(或稱俗民誌、人種誌)研究方法探討國際演講協會社團、社團活動以及其成員們三者之間的互動關係。本研究進行於九十八學年度第二學期，並持續一學期之久，當學期的四十五名社團成員為本研究的研究對象，其中四名社團成員為本研究的焦點研究對象，這四名焦點研究對象各擁有一到四學期不等的國際演講協會社團年資。研究資料透過半結構性訪談、現場觀察和文件資料收集而得，並根據情境學習理論做分析解釋。 研究發現此社團提供大學生課外的英語學習環境，並提供多樣化的資源和社群活動讓其成員透過自發性參與來加強英語溝通能力。四位焦點研究對象皆意識到社團所提供的學習機會並自發地參與社團活動以增進英語溝通能力; 然而，各成員參與社團活動的程度受其對社團的認同感、經驗和年資而有所不同。對社團有著較高認同與較深資歷的成員較常參與社團活動並表現出較多的自主英語學習行為，而這四位焦點研究對象在一學期的參與活動過程中也各自遭遇到問題與衝突。此外本研究也發現，身處學習社群情境脈絡的成員們各自相互影響其社群參與和自主學習，而社群所舉辦的社交活動有助於提升社群凝聚力，並隨之影響成員的活動參與和學習。最後，研究者也提出幾項在學習社群裡學習的重要議題並進一步提供建議，以作為學習社群與英語自學之參考。 / This study aimed to obtain an understanding of how a group of Taiwan college students as EFL learners made use of the attainable resources on campus, that is, a Toastmasters International club, to work on autonomous learning and develop English proficiency outside the classrooms. Ethnographical methodology was adopted to explore the relationship among the setting (the club), the activities (club activities), and the persons (the learners as members). All of the club members were the participants of this study, but four of them with diverse experiences in the club were invited to be the focal participants. The data collection stage lasted for one semester (fall, 2009). During this period, qualitative data were elicited from interviews, on-site observation, and document collection, and situated learning theory served as the theoretical and analytic framework. The findings of this study indicated that this club functioned as a valuable environment where members took advantages of its resources and social engagements to develop autonomous English learning. The four focal participants of this study were aware of the affordance of this club and valued the opportunities to engage in the club activities, but the degree of participation among them was influenced by individual commitment and the length of membership in the club. It was found that the seasoned members with higher commitment tended to participate more in the club activities, and they demonstrated more autonomous behaviors in developing language proficiency. During the process of participating in the club activities, all of the four participants encountered diverse problems and conflicts. In addition, members of the learning community exerted influence on one another members’ learning in terms of autonomous behaviors and degree of participation. Moreover, social contacts were of vital importance in strengthening the cohesiveness of the learning community, which influenced members’ participation and learning afterwards. It is suggested that, first, teachers and professors alike could encourage the establishment of learning community since the social and interactive support from the peers in the community is of vital importance for learners’ development of language proficiency and learner autonomy. Second, teachers and experienced members of a community could encourage help-seeking behaviors in an autonomous learning community and pay more attention to learners’ concerns of face-saving. It is hoped that this study could cast light on autonomous language learning community as a structure for future English education in Taiwan.