Complex sentence: It follows the rules of the International Ice Hockey Federation (IIHF) with modifications; athletes wear double-blade'sledges' instead of skates, which are designed so that the puck can pass beneath them.
Split into simpler sentences: It follows the rules of the International Ice Hockey Federation (IIHF) with modifications. Athletes wear double-blade'sledges' instead of skates, which are designed so that the puck can pass beneath them.