Here are three short, easy ways to say it:
Way 1: Fennec foxes and jerboas have fur on their feet. The fur stops their paws from burning on hot sand.
Way 2: These animals have fuzzy soles on their paws. The fuzzy soles keep their feet safe from the hot sand.
Way 3: Fennec foxes and jerboas wear furry feet like tiny shoes. The furry feet protect their paws from the hot desert sand.