Susanto, Irwan. 2010. An Error Analysis of Using Preposition in Descriptive Writing , A Descriptive Study on the Second Grade students of SMP Negeri 19 Tegal in Academic Year 2009/2010. A Final Project. English Department, Teaching Training and Education Faculty, Pancasakti University Tegal. First Advisor : Nur Antony ET, SS, M.Hum, Second Advisor : H. Sumartono, S.Pd. Key Words : Errors, Prep…