摘要：Nowadays, one of the most serious issues in teaching a second language is whether using first language is allowed or not during the teaching process. However, this critical issue is also important for Iranian teachers in teaching Prospect 1, a new course book for Iranian junior high school students. The study tries to consider the use of the first language (Persian) by both Iranian EFL teachers and learners in teaching Prospect 1. Moreover, teachers and students’ attitudes toward using Persian in English classrooms are scrutinized in this paper. To conduct this research, 248 Iranian EFL junior high school teachers, teaching Prospect 1 in Sabzevar, Khorasan-e Razavi Province, and sixty Iranian junior high school students participated in the study. The data were collected through two sets of questionnaires, for both the teachers and students. As the results of the study revealed, the tendency is toward using both L1 and L2 where Prospect 1 Course book is taught.
