Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to swim underwater without holding your nose [title] Get into the water and stand by the edge of the pool. [substeps] Standing by the edge of the pool will ensure that you feel secure while you go through the following steps. It is a good idea to stand waist-or chest-deep in the pool, whichever you are more comfortable with.

Ending1: [title] Bend forward, sliding your bottom along the edge of the pool and lifting your head. [substeps] Keep your elbows far from your body, the tops of your hands should be on the edge of the water. Ending2: [title] Slowly dunk your head underwater while blowing air out through your nose. [step] Exhaling through your nose is the main way to be sure that water doesn't get into it. Ending3: Stay below the waist level and keep your arms straight. Do not twist to open your chest, since doing this will make you dive into the pool headfirst and cause something else to happen. Ending4: [title] Keep your head and shoulders up while diving. [substeps] As you jump into the water, don't try to grab your nose, but instead hold your head high and your knees far apart.

Answer format: ending1/ending2/ending3/ending4