Original sentence: In June 2003, the university marked the fortieth anniversary of the "schoolhouse door" incident by hosting "Opening Doors," a three-day event to salute the individuals who took a stand for racial change at a crucial time in its history
Edited sentence: In June 2003, the university marked the fortieth anniversary of the "schoolhouse door" incident by hosting "Opening Doors," a three-day event to salute the sacrifice and commitment of the courageous individuals who took a stand for racial change at a crucial time in its history