Complex sentence: An instructor shows the boys how to ski using a "Pizza, French Fries" skill and later while practicing, an older skier, Tad, starts to accost Stan, calling him "Stan Darsh".
Split into simpler sentences: An instructor shows the boys how to ski using a "Pizza, French Fries" skill. An older skier, Tad, starts to accost Stan, calling him "Stan Darsh".