Abstract :
This study was conducted to answer the following questions (1) What are the types of grammatical errors committed by the eighth students of SMPK St. Theresia Kupang in the school year 2017/2018 in writing descriptive text? (2) What is the most type of grammatical error committed by the eighth grade students of SMPK St. Theresia Kupang in the school year 2017/2018 in writing descriptive text?. The objectives of the study are as follows: (1) To find out the types of grammatical errors in writing descriptive text made by the eighth grade students of SMPK St. Theresia Kupang in the school year 2017/2018. (2) To find out the most type of grammatical error in writing descriptive text committed by the eighth grade students of SMPK St. Theresia Kupang in the school year 2017/2018. The writer used descriptive method to describe students? errors in writing descriptive text. The subject of this study was the eighth grade students of SMPK St. Theresia Kupang, especially class VIIIB . They were consisted of 28 students and the writer only took randomly 20 students as the sample of the study. In collecting the data, the writer gave four topics to choose, they were ?My Friend, My Pet, My House and My Favorite Actor/Actress. The writing should consist of three or more paragraphs. The time allocation was 90 minutes. The result of analysis shows that (1) The eighth grade students especially class VIIIB of SMPK St. Theresia Kupang committed errors in writing descriptive text. They committed omission errors 67 (46%), misformation error 68 (46%), misordering error 7 (5%), and addition errors 5 (3%). (2) It is shown that the most common error is omission errors. Based on the result, the writer would like to suggest the following (1) The students should master grammatical aspect in producing a descriptive text by doing more practice in writing. (2) The English teacher should pay more attention on students? grammatical aspects of writing by providing exercise and drills particularly tenses.