Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to tape a knee [title] Sit down on a flat surface. [step] Great options include the floor or an elevated table, depending on what's available to you. Although a table may make it easier for someone else to wrap your knee, you need to make sure it's stable.

Ending1: This will make taping on a relatively flat surface be more convenient. [substeps] Never tape on a chair or your couch. Ending2: [title] Elevate your knee with a rolled towel or similar item (optional). [step] This should put your knee at a 30 degree angle. Ending3: If you're too high for the person to wrap their knee, they may get frustrated and cut themselves. You want to make sure your tabletop is stable and won't buckle or bend if someone cuts into the wood. Ending4: [title] Make a straight line along the entire length of your knee. [step] For general comfort, this line should be at least a foot (0.6 m) across.

Answer format: ending1/ending2/ending3/ending4