Utilizing Corder's (1967) Error Analysis framework, this study investigates frequently encountered morphological errors made by fourth-year university students in their academic papers. Concerning English as a second language, morphological errors influence not only how they write essays but also the grammatical structure and word meaning. The study uses a mix of methods integrating qualitative and quantitative analysis to determine, categorize, and fully comprehend the most often occurring morphological errors. The study engaged thirty students from the department of English at Tobruk University. We examined each student's essay closely applying error classification following collection. The majority of the morphological errors were in misformation (53.13%), addition/omission (26.98%), misordering (9.13%), overuse (7.46%), misselection (2.48%), and substitution (0.82%). These spelling, grammar, and word structure mistakes demonstrated how much the students need to concentrate on language training to enhance their essay writing skills.
Keywords: academic papers, mixed methods, department of English, Tobruk University