English Comparative Forms in Iranian Textbooks Compared to Textbooks Developed by Native Material Developers

In the introductory stages of language learning, students are exposed to comparative forms explicitly taught in their textbooks. As Knoch (2004) mentioned, this is accomplished by teaching the comparative form of the adjective generally directly followed by a than clause. This study aimed to compare differences between native and nonnative material developers with regard to the coverage of comparative forms. In doing so, two corpora of high school books and Interchanges were developed and juxtaposed. The data were gathered by scanning the books and converting them into computerized forms. The data were then analyzed by the frequency percentages of the forms and further examined and compared as well. The results revealed that there was a significant difference between the two corpora with regard to the coverage of comparative forms.