The aim of this research is to eliminate spoken language elements in the written expressions of secondary school 7th-grade students. In this study action research was employed as a research design. The participants of the study are 19 students at the 7th grade who are studying in a public school in the city center of Erzurum were selected purposefully. The study was carried out in the fall semester of the 2019 - 2020 academic year. The research data were collected from students’ written expression studies. Spoken language elements in students’ written expression studies were examined with content analysis. In the study of 10 weeks duration in order to improve students’ reading writing and listening simultaneously with data collection process given creative assignments speech and creative writing activities have been conducted. The weekly developments of the students were quantitatively monitored with the checklists prepared by the researcher. According to the findings of the study, 33 error types related to the speech language elements in the students’ written expression studies were determined. The types of errors detected were analyzed under three themes: “errors encountered at the level of phonetics”, “errors encountered at the level of morphology” and “errors encountered at the concept sign level”. According to the themes examined, students made the most mistakes at the phonetics level. In the written expression studies of the students, the features of the spoken language that mostly originate from the local dialect are observed, besides, the features of the spoken language that do not comply with the standard Turkish have been determined. According to the results of the research, a decrease was observed in the speech language elements determined in the students’ written expression during the application compared to the weeks. It is concluded that writing activities supported by speaking, reading, and listening techniques contribute to improving students’written expression.