THE STUDENTS ABILITY IN USING STANDARD AND NON STANDARD LANGUAGE IN AL-MUJADDID BOARDING SCHOOL SABANG

English is an international language that is important to learn. In general, language is divided into two, namely formal language and non-formal language. Formal language is an official language that has standardization in its use with a standard form and is usually applied in formal forums. While non-formal language is a language that does not have standardization in its use and is applied according to the region. Pesantren is a traditional Islamic educational institution in Indonesia that plays an important role in developing students' language skills. This study aims to determine the ability of students at Al-Mujaddid Islamic Boarding School in using standard and non-standard languages. The study used a mixed methods approach, which combines qualitative and quantitative methods. Data were collected through performance test and surveys to assess students' linguistic abilities in using formal (standard) and informal (non-standard) language.Based on the results of the study, the majority of students have difficulty in distinguishing and using formal and informal language correctly, as evidenced by the 69% incorrect answers in the survey. Although students can deliver speeches well using texts or dictionaries, their ability to use language independently is still low. In daily activities, students tend to use formal language even though the situation is more suitable for informal language, showing a lack of understanding of language use according to context.