Imelda Susanti Tanggu Pengarang JOSUA BIRE Dosen Pembimbing 1 Josua Bire Penguji 1 Alexander Home Kabelen Penguji 2 Yanpitherzon Liunokas Ketua Penguji

This thesis is entitled A Study On Grammatical Error Committed By Second Semester Students Of English Study Program Of Nusa Cendana University in Academic Year 2020/2021 In Using Simple Past Tensen In Diary Writing. The problems of this study are: (1). What are grammatical errors committed by second-semester students of the English study program of Nusa Cendana University in the academic year 2020/2021 in using simple past tense in their diary writing? (2) What are the causes of those errors? The aims of this study are: (1) To identify grammatical errors committed by the second-semester students of the English study program of Nusa Cendana University in the academic year 2020/2021 in using simple past tense in their diary writings (2) To describe causes of those errors. This study used the qualitative descriptive method. The research was conducted in University Nusa Cendana of English study program. The subject of this research was second-semester students of the English Study Program of Nusa Cendana University in the academic year 2020/202. There are 37 students the writer choose 20 students out of 37 was, because only 20 students, who were willing to provide the data. The researcher used diary writing tasks and interviews to collect the data. The researcher used two techniques in collecting the data instrument and interviews. The writer used two data analyses identifying and describing. The researcher used descriptive qualitative to describe the students’ simple past tense. The use of simple past tense was described in detail in this research based on the result of the students' interviews. The researcher analysis and write the mistakes of the students. The result of data analysis shows that the students have grammatical errors and they are still confused in using simple past tense from the test that has been done by students, the researcher used two methods, namely tenses of error and correct sentences. Then the researcher has clarified and concluded that some students were still incorrect in using simple past tense in writing diaries. Moreover, there were still many students who are confused about what are a verb and an irregular verb. Keywords: Diary Writing, Grammar, Grammatical error, Simple past tense, writing