FARLIUS WIBOWO Pengarang ELISNA HUAN Dosen Pembimbing 1 LENI AMELIA SUEK Dosen Pembimbing 2 Elisna Huan Ketua Penguji Leni Amelia Suek Penguji 1 MERLYN K NELLOE Penguji 2

The aims of this research were to find out the ability of the students in mastering adjective clause of the eleventh grade students of SMAN 5 Kupang in the academic year 2022/2023 and to find out the difficulties in mastering adjective clause faced by eleventh grade students of SMAN 5 Kupang in the academic year 2022/2023. The researcher used the descriptive qualitative method. The subject of this research was 30 students from eleventh grade students of SMAN 5 Kupang in the academic year 2022/2023. This research used test and questionnaire to collect the data. The result shows that the total score of the test was 1520, The mean of the score was 50, 6 (poor). The student’s difficulties in mastering adjective clause were the comprehension, using unnecessary pronoun, and using the wrong relative pronoun. In conclusion, the students’ ability in mastering adjective clause was poor category and the students had difficulties in mastering adjective clause. It indicates that the students did not understand well about adjective clause. Some suggestions were given to the teacher, to the students, and the other researcher. Keywords: Analysis, Difficulties, Mastering, Adjective Clause