Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to stay safe when using a trampoline [title] Place your trampoline in a flat, open area. [step] The ideal location for your trampoline is one out in the open, away from any trees or objects that you might hit while jumping. You also should keep the ground clear for several feet around the trampoline.

Ending1: [title] Brace yourself for the falling trampoline. [step] Many trampolines will have rolls, or mats that is meant to cushion impacts. Ending2: [substeps] While trampolines are a great way to avoid falling, keep in mind that an uneven surface can send a serious risk of a fall. The trampoline may, for example, injure your arms or even snap a broken railing. Ending3: [substeps] Removing any objects within 8 feet (2.4 m) of the trampoline in all directions. The ground under and around the trampoline should be as level as possible to keep people from jumping too high or causing the trampoline itself to flip over. Ending4: Make sure the surface is flat and easy to clean. [title] Allow someone to hold the trampoline while you complete the first few steps.

Answer format: ending1/ending2/ending3/ending4