Notice how they make contact with the ground as they roll from heel to toe and then travel through the air to stride forward.

留意它们是如何从脚跟到脚趾接触地面，然后离开地面向前迈进。

youdao

Walking is also called heel and toe walking. The heel of the form foot hits the ground just before the toe of the back foot leaves the ground. So one foot is in contact with the ground at all times.

竞走也称作足踵和足趾走。前足踵着地后足趾才能抬起来。因此，必须有一只脚始终着地。

youdao

Nail polish (toe nail polish is also the case) is made of synthetic resin dissolved in solvent, mixed with pigments to color and blend, and therefore it has cut off contact with the external role.

指甲油(脚趾甲油亦如此)就是由合成树脂溶解于溶剂中，为了着色而掺入颜料混合制成的，因而便有着隔断与外间接触的作用。

youdao

They calculated the force in question from the contact area of the toe, and found that toe pads were still sticky two minutes after the sliding had stopped, long after the point when, according to their estimate of its viscosity, all the mucus would have drained away.

ECONOMIST: How tree frogs keep their grip

Thus some parts of a frog's toe pad are in direct and dry contact with whatever they are standing on.

ECONOMIST: How tree frogs keep their grip