Complex sentence: Burnham was one of the founding leaders of the People's Progressive Party (PPP), which was launched on January 1,1950; the Indo-Guyanese labor leader Cheddi Jagan became PPP Leader, while Burnham became its Chairman.
Split into simpler sentences: Burnham was one of the founding leaders of the People's Progressive Party (PPP), which was launched on January 1,1950. The Indo-Guyanese labor leader Cheddi Jagan became Leader of the PPP and Burnham became its Chairman.