Error analysis of high school students’ grammatical error on english report presentation at man Kota Surabaya

Grammatical errors are common to be found or made by second-language learners. This study investigates the categories and origins of errors made by students during presentations, examining the types of errors observed and their underlying causes. This research uses a qualitative design and adopts a descriptive approach. The subject of the research is students of an Islamic state high school Surabaya grade tenth, recommended and chosen by the teacher, this research took class X-J as the research subject with a total of thirty students in the class, the researcher gathered the data for the research through the students’ presentation where the researcher recorded the presentation to analyze the errors. After analyzing presentations by students, the researcher found the most common mistake was using the incorrect verb tense, which led to 54.54% of all error types. This type of error occurs because the students are unable to apply the proper verb form for specific tenses, the researcher also found out that the main reason for these mistakes is "overgeneralization." This happens when learners generalize grammar rules too much, this leads to errors like using the wrong verb form in certain situations. It is suggested that the teacher solve the problem by drilling students' grammar knowledge on the specific areas of error that are pointed out in this study.