Intercultural differences and their role in teaching English have been a point of research for decades. While some believe that it is useless in structured setting, some others consider it advantageous without having the disadvantages such as anxiety in the real context. The present study tries to investigate some significant cultural differences between Iranian and American/English culture some of which are selected from Brook's (1986) list and some others based on the researcher's experience. The results indicate significant differences in 15 out of 17 head categories. The information may help some 86 researchers including teachers interested but not knowledgeable enough in the intercultural differences.
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