為了解決目前我國英文學習環境無法提供個人化英文口語會話練習的機會,因此本研究提出一個英文對話式學習夥伴系統(English dialogue companion system,又稱EDC)以結合對話系統和學習夥伴的功能,提供國小學童學習英語時,有練習口語會話對象。本研究對話機制的語意分析部分,採用Wu等人(2008)發展多層文字支援向量機來分類Predicate-Argument結構的實作方式,再將取得到的語意分類的結果至知識庫中取得回應句。此外,還設計了三個學習活動來加強國小英文口語學習策略,包含選擇學習夥伴、會話階段以及教學階段。學習者可以個別擁有擬人化對話式學習夥伴,並且學習夥伴可以陪伴他練習英文會話,學習者還可以指導學習夥伴新的學習內容。本研究並執行田野實驗以探索EDC系統對學習者英文學習成效的影響。實驗結果顯示控制組和實驗組間沒有顯著差異存在,然而受試者在ARCS動機量表、以及代理人角色教材(API)量表中,都給予EDC系統使用動機上正面的評價。而且本研究根據研究結果提出未來設計國小學童英文對話學習夥伴四點參考:學習夥伴的角色設計、學習者程度分級、系統提供鷹架輔助、以及遊戲功能,期望在未來研究工作上,可以給予學習者更貼切的幫助。 In this paper, we proposed an English dialogue companion system, called EDC, using predicate argument structure by Support Vector Machine (SVM) classifier for semantic analyzer in order to support elementary students for learning English one on one. Three phases of learning activities were designed to enhance the English learning environment, which are the choice of learning companion phase, the conversation phase, and the teaching phase. Firstly, a learner selects an animated figure as her/his own learning companion. Secondly, a learner can chat with the EDC system in English by keyboard or microphone. Thirdly, a learner can teach new vocabularies or sentences to the learning companion. A between-subject design experiment was conducted to evaluate the effectiveness of the EDC system in terms of English achievement, motivation, and cognitive characteristics. Results of this study showed that there is no significant difference between the experimental group and the control group on English achievement. However, the motivation and cognitive characteristics of the system have been very positive. Overall, the subjects agreed that the system is useful and helpful in English learning.