effectiveness of web-based tools in learning idiomatic expressions: a call study

With the development of technology and due to the covid-19 pandemic, most of the elt courses in iran have shifted to online learning since march 2020. therefore, this study aimed to determine the effectiveness of four online technological tools for teaching idioms. to this aim, 106 pre-intermediate learners of english took part in the study. a language proficiency test was administered to them to ensure the homogeneity of the sample. a total number of 80 students who had been selected as the final participants were randomly assigned to four experimental groups: in group a, concept maps of the same idioms were drawn with the help of an online mind-map maker. group b was presented with online flashcards which included definitions and examples of idioms. group c received etymological elaboration from an online dictionary of the origins of idioms, and group d listened to online audio stories of all the idioms. each group of participants received the treatment for 12 sessions and took part in the pretest, posttest, and delayed posttest. results of a one-way anova indicated that the most gains were achieved by story-telling. the findings imply implications for teachers, syllabus designers, and materials developers in using appropriate instructional methods for teaching idioms.