Complex sentence: Due to the international background of the Lycée International's student population, some students enter the Lycée... entering students who are not fluent in French are placed in a one-to two-year French language immersion program called "Français spécial".
Split into simpler sentences: Due to the international background of the Lycée International's student population, some students enter the Lycée International without French language fluency. Entering students who are not fluent in French are placed in a one-to two-year French language immersion program called "Français spécial".