本研究旨在建立一套英語教育真切性(authenticity)的診斷模式。依據心理詞彙量的建構理論，學習第二語或外國語過程中，輸入(input)的資料愈真切(authentic)亦即愈契合實際生活中的使用情形，學習的效果愈佳。在臺灣學習英語的途還是以文字書寫的型態為主，因此建立一套診斷「讀本式教材」真切性的模式，在英語教學與教材的編製雙方面，皆有實質的貢獻。透過電腦程式的輔助，字頻語料庫的建屯已能提供研究者大量的真切語料(authentic corpus)；本研究即利用Cobuild出版的字頻表，比對部編本國、高中英文課本(國立編譯館所編寫)，以及教育部頒佈之常用英文詞彙，分析英語課本的真切性。在此教改之際，教科書已開放予民間業者出版，教材選擇需要更多參考依據。希望藉著字頻分析比對診斷模式的建立，提供關心英語教學的人士一套可行、合理，且充分利用電腦科技所提供之便利的教真切性分析法。

　　　　　This study aims to build a diagnosis model for authenticity of English teaching materials. According to psycholinguistic theory on mental lexicon constructs, the more authentic (i.e. identical to real life usage) the teaching materials of a second/foreign language are, the better they would help language learners. In Taiwan, an EFL environment, most input is in written form. Therefore, if successfully applied to analyzing English reading materials, this model should be beneficial to both English language instruction and curriculum design. Databases have been providing researchers with a tremendous amount of authentic corpus. This study compared the word frequency counts published by Cobuild with the vocabulary listed in Taiwan high school English textbooks and the most frequently used vocabulary list (both approved by the Ministry of Education) to diagnose their degree of authenticity. It is hoped that his model can help English educators in designing and selecting authentic teaching materials.