Complex sentence: She attended high school at the Ecole sociale de Karubanda where she became friends with Agathe Habyarimana, the future wife of Juvénal Habyarimana, who became President of Rwanda in 1973.
Split into simpler sentences: She attended high school at the Ecole sociale de Karubanda. There, she became friends with Agathe Habyarimana, the future wife of Juvénal Habyarimana, who became President of Rwanda in 1973.