Document Type : Original Article
Department of English Language and Literature, Semnan University, Semnan, Iran
< p>This study investigates the prevalence of a number of major issues and concepts in the field of language teaching in the related research literature and reports published from 1968 to 2018. The purpose was to give a taste of the changes that came about in language teachers'' concerns over these years. The researcher first selected a large number of high-profile terms in language teaching by browsing through the tables of contents and indexes of language teaching textbooks. He, then, shortlisted these terms subjectively or in informal consultation with language teaching experts. Then, the abstracts available from nine language teaching journals published from 1968 to 2018 were collected and assigned to four-time spans: 1968-1990, 1991-2000, 2001-2010, and 2011-2018. The abstracts were processed for frequency tagged words and n-grams, which produced two lists for each span. Using these lists, the incidence of the target terms in the four-time spans was established. The study presents normalized and comparable statistics about the frequency of occurrence of the target language teaching ideas in the research literature of the four-time spans and refers to examples of insights and messages which can be drawn from these data.