At higher education settings, summarization skills are essential to academic success. However, research on summarization appear to have been relatively neglected, and consequently "many more are needed". To this end, 120 EFL students of Shahid Chamran University of Ahvaz,Iran were selected: the three experimental groups were subjected to the task-based language teaching principles in the treatment. two reading comprhension texts ( one as a pre-test, the other a post-test)were assigned to the four groups involved, and they were all required to write up two summary protocols for each text they read, one in English, and another in Persian. In the experimental groups ,summary writing was mediated by a particular teaching task while for the control groupthere was no mediating task. Afterwards, the performance of all subject groups was evaluated based on a cross-linguistic evaluation scale to determine a)if task-based language teaching had any significant effect on learners' reading comprehension and b)if the L1 of the subjects contributed to a better comprehnsion of the texts they read.Finally,the conclusions and pedagogical implications of the research for EAP courses were highlighted.