Pasaribu, N.A.M. 2022. Contribution of Mastery of Sociolinguistic Concepts to Pragmatic Skills by Students of Free Mathodist 1 Private Junior High School Medan 2012/2013 Academic Year. International Journal of Basic and Applied Science. 10, 4 (Mar. 2022), 145–153. DOI:https://doi.org/10.35335/ijobas.v10i4.70.