本研究的目的為探討學習者具有選擇閱讀材料的權利,是否影響他們閱讀時的詞彙偶發學習(incidental vocabulary learning)。另外,本研究也進一步探究學習者對於閱讀材料的感興趣程度與詞彙偶發學習之間的關係。 本研究包括了兩個實驗。在實驗一(study 1)與實驗二(study 2)中,研究者都將受試者分成兩組:自由選擇組(self-choice group) 和 系統分配組(system-assigned group)。實驗一的結果發現自由選擇組的學生在詞彙測驗的表現較系統分配組的學生好;自由選擇組的學生對於閱讀材料的興趣也明顯較系統分配組的學生高。但在實驗二中,兩組學生不僅在詞彙測驗的表現沒有顯著的差異,對於閱讀材料的感興趣程度也沒有顯著差異。本研究認為可能是興趣(interest)導致兩次實驗的結果不一致。最後,本研究進一步提供相關的建議,作為未來研究的參考。 The main concern of this study is to investigate whether second language incidental vocabulary learning from reading is affected by whether the learner is allowed to choose the reading material as opposed to being assigned the material to read. It also examines effects of students’ level of interest in the reading material on their incidental vocabulary learning. Two experiments are reported in the thesis: study 1 and study 2. In both study 1 and study 2, participants were divided into a self-choice group and a system-assigned group. Students of the self-choice group could choose reading materials freely. Students of the system-assigned group were assigned passages. The result of study 1 shows that the incidental vocabulary learning of the students of the self-choice group was better than that of the system-assigned group. Also, students’ interest level of self-choice group was stronger than those of the system-assigned group. However, the results of study 2 shows that students of two groups were not significantly different in terms of not only target word tests but also interest levels in reading materials. Interest might be the main factor that causes the inconsistent results in two studies. The study provides suggestions and some directions for future research to explore this issue further.