Original sentence: In fall, 1997, a group of 100 volunteers climbed Cowles Mountain after dusk to commemerate the 100-year anniversary of the school by using flashlights to once again outline the "S" on the side of the mountain
Edited sentence: In fall, 1997, a group of 100 volunteers climbed Cowles Mountain after dusk to commemorate the 100-year anniversary of the school by using flashlights to once again outline the "S" on the side of the mountain