2. THE DEBATE The idea of ​​including L1 in the language teaching system has been debated in recent years. Strong anti-L1 advocates suggest a complete ban on L1 in classrooms, while many others see L1 as a tool for better student learning of TL. This section will highlight the arguments for and against the use of L1 in classrooms, as well as other evidence demonstrating the benefits that the native language brings to the language learning and teaching process.2.1 ARGUMENTS AGAINST THE USE OF L1 IN CLASSROOMSIn the 20th century, avoidance of using L1 in the classroom dominated the minds of teachers; it has also been implemented in many language teaching policies and guidelines (Cook, 2001). Thornbury (2010) listed a set of arguments against the use of L1 in L2 classrooms, mainly because translating the L2 into another language would have negative effects on the students' learning process. He pointed out that the use of L1 would result in learners' cognitive dependence on their mother tongue to the detriment of developing autonomy in learning the mother tongue. Although the two language systems are not equivalent in many respects, students may be aware of the notion of equivalence of the two languages ​​if translation is used to convey meanings. Some argue that using translation to convey the meaning of the TL is more effective and more memorable. However, Thornbury (2010) sees the opposite. He said that the simple and straightforward way of translating will make L2 knowledge less memorable since the process lacks mental effort to work out meanings. Many researchers like Krashen (1985), Harmer (2007) and Turnbull (2001) point out that in most cases of EFL, (English as a Foreign Language), a teacher's English proficiency..... .middle of copy......L1 for instructions and ratings to avoid confusion. On the other hand, teachers prefer to use L1 for more efficient work. approach to teaching grammar and checking student understanding. Macaro (1997) noted that teachers often lack enthusiasm when it comes to using the target language to explain grammar. Many students have difficulty learning grammar, especially those whose L1 system is completely different from that of the TL. The L1 may be more effective, particularly when a teacher wishes to discuss the learning contract with their students or attempts to explore the needs of their students, particularly those at the lower level (Harmer, 2007). Data provided by Harmer (2007) also indicates that the classroom environment can be improved through the use of L1 to establish a positive social relationship with students, which ultimately leads to a more effective teaching process..