Complex sentence: A class president is usually the leader of a student body class, and presides over its class cabinet or organization within a student council, in a grade school class presidents are generally elected by the class, a constituency composed of all students in a grade level.
Split into simpler sentences: A class president is usually the leader of a student body class, and presides over its class cabinet or organization within a student council. In a grade school, class presidents are generally elected by the class, a constituency composed of all students in a grade level.