本研究旨以任務複雜度進行教學實驗，並且探討任務複雜度對零起點華語學習者口語學習成效之影響，希望藉此提高零起點口語學習者之口語學習成效、對比經任務複雜度不同之教學後，口語學習成效與學習動機之間的關聯。本研究以實驗法和訪談法進行研究，正式施測以前，編寫任務型教案，並且由研究者布置任務複雜度較高的教學任務教學實驗組，另一名教師教學對照組；研究對象為美國大學中文課中非亞裔、沒有漢語背景的零起點之學習者共二十名，實驗組十名，對照組十名。本研究之教學實驗為期十五週(共四十五小時)，第一週開始進行教學實驗，第七週時進行中測，第十五週進行後測，根據任務複雜度的不同進行教學實驗後，分析數據後得到以下結果：任務複雜度高的確能夠提高零起點學習者口語學習成效。任務複雜度和口語學習成效的相關性可從三方面看出：(一)任務複雜度高有效提高學習者語言技能精準度、互動表達及整體表達能力。任務複雜度高之任務型課堂教學，學習者語言技能和溝通技能都顯著優於任務複雜度較低的任務教學活動。(二)複雜度較高的任務以分組活動方式進行可使學習成效良好。任務導向的分組活動設計，有效提高學習者信息交流和多向信息注意力。(三)以任務複雜度高教學，使學習者口語學習成效提高，語言表達能力更好，因此對學習者之學習動機有正面影響，進而帶動學習者繼續學習中文的意願。此外，本研究發現，任務型教學法能夠適用於零起點班級，任務複雜度高能夠有效提高口語學習成效。
Task-Based Approach (TBA) to teaching foreign languages has not been applied to true-beginning language students. This study explores the effects of TBA and varying de-grees of task-complexity on the effectiveness of true-beginning Chinese students’ oral lan-guage learning abilities. I aim to improve student motivation and verbal learning outcomes for beginning students though different degrees of task complexity. Direct experimentation was conducted on 20 American college-students with non-Chinese background enrolled in true-beginning Chinese courses: 10 students belonged to the control group, taught by a sepa-rate teacher using simple tasks as pedagogy, while the other 10 underwent the experimental teaching method, which lasted 15 weeks and a total of 45 hours. Evaluations were con-ducted during the seventh and last week of classes to measure progress. The overall conclu-sion is that highly complex tasks do indeed improve oral languages skills of true-beginning Chinese students. Three other important insights can be obtained from the relationship be-tween oral language skills and complex student tasks: 1) complex tasks demonstrably elevate students’ language accuracy rate, abilities to interact and overall oral expression performance; 2) students’ learning performance can be further improved by dividing highly complex teaching tasks into separate group assignments or Group Work; 3) since highly complex tasks improved students’ language abilities, they are, consequently, more motivated and eager to continue learning Chinese. Moreover, the results confirm that TBA and highly complex tasks can be effectively applied to true-beginning Chinese classes.
