語用能力是語言習得成功重要的一環，但在臺灣高中的英語教學中卻未受到重視。教師的語言行為對於學生在語用和文化價值觀方面有很大的影響，所以檢視英語教師和外籍教師在語言行為是否有相似的策略有其必要性。本文著重在高中英語教師和外籍教師祈令語使用之比較，以瞭解臺灣英語教師的語言行為策略之使用和外籍教師有何異同，並進一步探討文化對語言行為之影響。 本研究利用語文完成測驗問卷(Discourse Completion Task Questionnaire)收集受試者之語料，共有50位本國籍及30位外籍高中英語教師參與研究。問卷資料主要以卡方檢定(Chi-square)，並輔以質性分析兩組受試者之回答。 研究結果指出兩組受試者均使用最多非傳統間接策略(non-conventionally indirect strategies)；但是，本國籍英語教師比外籍教師採用更多直接策略(direct strategies)，外籍教師則比本國籍教師常使用其他策略(other strategies)，例如接受學生的行為或私下約談處理。本研究證實文化的確在語言行為中扮演重要角色，更建議中外籍英語教師均有責任教導學生正確的語用知識，以協助他們在不同情境中和他人成功地溝通。

This study examines the beliefs of foreign language teachers regarding the relative positions of native and nonnative speakers in foreign and second language education. In particular, I am concerned with the idealization of the native speaker in this context and the foreign language anxiety that may occur in nonnative speaker language teachers if they internalize this idealization. I collected data from 29 college-level Arabic and Hebrew teachers using four methods: (1) a questionnaire on their background and beliefs regarding native and nonnative speaker language teachers, (2) a version of the Teacher Foreign Language Anxiety Scale (Horwitz, 2007), (3) a one-on-one interview, and (4) class observation. By and large, study participants believed that native speakers, because of their nativity, have reached higher levels of linguistic and cultural proficiency with relative ease, and as a result are more readily granted credibility as teachers of their native language. Participants believed that nonnative speakers are more empathetic and understanding of their students' problems because of their own experience and efforts as students of the language. With regard to foreign language anxiety, the main sources of anxiety among the nonnative speaker participants were the fear of making mistakes (and losing credibility as a result), of not having the authority to speak on cultural issues, of not being hired when competing with native speakers, and of addressing professional audiences. Native speakers feared that they cannot anticipate or understand as easily as nonnative speaker teachers the difficulties their students have in learning their language, because they cannot relate to their experiences in the same way. Neither group, however, reported feeling particularly anxious overall. I argue that anxiety was minimal for both groups because of specific steps that participants have taken to overcome the perceived disadvantages of their group and thereby bolster their confidence. Participants reported gaining confidence through some combination of the following factors: (1) gaining experience and education, (2) improving their linguistic and cultural proficiency, (3) presenting the persona of a credible language teacher through extra preparation and language choices, (4) receiving external validation, and (5) realizing that everyone can learn from and teach others. / text