Despite many ELT experts' opinions that while teaching a foreign language one should not use the mother tongue in the classroom, new researches show that sparing use of the mother tongue can be effective for the L2 learners. It is true that the 6- year compulsory English education of the school graduates of Saudi Arabia is not quite up to the mark. They can hardly write a simple sentence in acceptable English, let alone a paragraph or a free composition. The spoken and listening proficiencies remain even worse. This study examines the students' and teachers' attitudes to the use of L1 in EFL classrooms at Najran University English Department and Preparatory Year, male and female sections. Little research has been done on English language teaching and learning in multilevel language classrooms in the context of the universities in Saudi Arabia in general and Najran University in particular. The study employed questionnaires to obtain the participants' attitudes to L1 use at different levels of teaching and learning. The findings suggest that L1 may play an effective role in the language classrooms at all these levels. L1 has been found useful for explaining the meaning of difficult words and use of grammar. Even a comparative study of the syntax of L1 and L2 may be useful, because this often saves students from confusing their L1 syntax with L2. The paper provides recommendations for a successful and restricted use of L1 in multilevel language classrooms and suggests that more research is required in this field to find out a feasible, if not permanent, solution. (Contains 22 tables.)