Please choose the correct ending to complete the given sentence: Cars & Other Vehicles: [header] How to ride a bike with one hand [title] Make sure that you're good at riding a bike with two hands. [step] You should be able to be balanced, and you shouldn't be falling off at all. If you can't ride with two hands, you won't be able to ride with one.

Ending1: [title] Demonstrate how to lead by guiding with one hand. [step] You should always lead with your other hand but with the bottom of your hand placed on the pedal. Ending2: [substeps] On bikes, positions like wheels, handlebars, or pedals are less important. You should feel like you're running headfirst on the bike when you don't have two hands. Ending3: [title] Get on your bike and start riding. [step] This time, loosen the grip of one hand (whichever one you feel more comfortable doing). Ending4: Lean on a chair, a backpack, or whatever you're not comfortable doing. Ride with one hand to hold your torso against the bike and to get off calmly.

Answer format: ending1/ending2/ending3/ending4