Ode switching between Arabic and English among three generations in Saudi Arabia.

My study focuses on code switching used by three generations and how the frequency of using code switching differs from one generation to another. It also focuses on the reasons and motivations behind using code switching. I would like to have literature review about the role of speakers age in code switching and literature review about the reasons lead to code switching. I also would like to have at least 30 references most of them from the top journals in linguistics.