3. When the rope falls to the ground, it is best to touch the ground less or even not. Because the rope will deform for a short time when it falls to the ground, it is difficult for the jumper to escape. And there is resistance, and I can't shake fast. This requires the rope thrower to be taller. Because if the rope doesn't touch the ground, the height of the sling will decrease accordingly. If the person who throws the rope is tall and the person who jumps is short, the height of the rope can be made up when throwing the rope, so that the person who jumps can escape more easily.