A dissertation submitted in parial fulfilment of the requirements for the award of the degree Licence en Langue et Littérature Anglaises.

RESUME,

This present work, deals with the impact of code switching and code mixing on the development of the oral fluency in English in the Department of English Language and Literature in the University of Burundi. This study was carried out in the Department of English Language and Literature precisely on some students from third and fourth years who served as population for the research. The purpose of this study is to look for possible solution in order to improve the oral fluency in English. To achieve this goal, I distributed a questionnaire to some students from third and fourth years in order to get reliable and verifiable information. After having collected and analyzed the data, I realized that code mixing and code switching are synonyms of the lack of practice since the speak do not speak exclusively one language for a time and therefore have a negative impact on the development of the oral fluency in English on the behalf of students. After having realized the negative impact due to the lack of practice of English language, I have suggested to students some solutions such as taking at least 30 minutes of practicing English per day by making discussions in English language with their classmates. In addition, the recommendations are also directed to different actors who can contribute to the development of the oral fluency by helping students to get more opportunities of practicing the English language. Those actors are university authorities, the government, the students themselves and future researchers.