A Suggested Program Based on Grammatical Context Engineering to Develop the Grammatical Structure Skills of the Arabic Sentence of Preparatory Stage Students By Dr. Salwa Hassan Mohamed Basal Dr. Essam Mohamed Abdo Khattab The present research aimed at developing the grammatical structure skills of the Arabic sentence of the second grade preparatory students through a suggested program based on grammatical context engineering. To achieve the previously mentioned aim; the researchers determined the grammatical structure skills needed for the second grade preparatory students. A grammatical structure skills' test was also prepared. The quasiـexperimental design was used. The sample was divided into two groups; experimental group and a control group. The suggested program based on grammatical context engineering was designed. A teacher's guide and students' worksheets were also prepared to be used in practicing the grammatical activities needed to develop the aimed skills. The research instrument was pre administered to the two groups then the program was applied during the second term of the academic year 2020/2021. After that the research instrument was post administered to the two groups. Results indicated that there was statistically significant difference at the level of (0.01) between the mean scores of the experimental group and that of the control group in the post administration of the grammatical structure skills' test as a whole and for some subـskills favoring the experimental group. The researchers recommended utilizing grammatical context engineering to teach grammar for students in different stages as the traditional method in teaching grammar weakened the grammatical structure skills of the preparatory stage students. Key Words: Grammatical Context Engineering, Grammatical Structure Skills, Preparatory Stage Students