Before revision: Soon after they asked that she teach a class at the Canterbury Court apartments, and it was there that she noticed her students, aged 70 to 95, were having difficulties with balance, coordination and fatigue, and she began to adapt the program by introducing the chair.
After revision: Soon after they asked that she teach a class at the Canterbury Court apartments, and it was during these classes that she noticed her students, aged 70 to 95, were having difficulties with balance, coordination and fatigue, and she began to adapt the program by introducing the chair.