This study was conducted to find out the effectiveness of my writing instruction and prepare for the following writing instruction in a graduate school context in the Southern part of South Korea. To achieve the goal, three research questions were raised and answered in a given order; 1) Participants of the study (N=5) show no progress in writing in terms of accuracy and fluency, 2) The most frequently appearing errors appeared in the pretest were Agreement (Noun in numbers) > Article > Cubing > Main verb (Transitive vs intransitive). 3) As to the remaining errors in the posttest, Agreement (Noun in number) > Cubing > Meaning > Mechanics (Period) > Sentence types (S+V) errors survived at the end of the semester. Agreement (Noun in number), Cubing, and Sentence types (S+V) errors survived. Compared to the previous teaching context, my new students at a new university, called P University, show a unique way of making errors in writing. Based upon the findings of the study, instructional intervention, including writing, was suggested as the form of the quizzes in the future.