Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to flip on the trampoline [title] Get supervised training first. [step] Using a trampoline can be very dangerous, so it is best to train first in a safe environment. Training happens in lessons for competitive sports including gymnastics and diving.

Ending1: There, a teacher or coach can help you learn how to use a trampoline properly. [substeps] Improper use of a trampoline can lead to severe head and spinal injuries. Ending2: Make sure you choose an area where you can get supervised training before you move on to a more aggressive and demanding sport like spinning or the super smash hose. [title] Get the proper safety equipment before you start practicing. Ending3: [substeps] If you're just starting out on the trampoline, start in there with more advanced techniques and forms. Once you get comfortable working with many different jumping techniques, start working on rope jumping. Ending4: It is a requirement during or after the half jump and half leap and is optional. However, adults may be okay with you practicing your right turning technique for a short period of time.

Answer format: ending1/ending2/ending3/ending4