Rifki, M., A. Rusmanayanti, N. Chandra, and F. Mu’in. “A Study on The Students’ Errors in Using Simple Present Tense”. LINGUA EDUCATIA, Vol. 1, no. 2, Dec. 2019, pp. 93-14, http://jtam.ulm.ac.id/index.php/gej/article/view/294.