It's a material force that his rhetoric challenges and relies on, gives him a means of getting off the ground, and a means of always getting back to it, too.

这是他的修辞所挑战的并且依赖的物质力量，这种力量给他离开地面的方法，也给他回到地面的方法。

耶鲁公开课 - 现代诗歌课程节选

You apply a force and the material will resist it until you have a force great enough to break the bonds.

如何你对它施加一个外力，材料能够承受,除非这个外力足够强大去打破键。

麻省理工公开课 - 固态化学导论课程节选

Whenever there is a force, it can be traced back to a tangible material cause, which is all the time a force of contact, with the exception of gravity.

如果有作用力,那它一定能找到一个明确的实体施力物体,也就是无论何时物体受的都是接触力,引力除外

耶鲁公开课 - 基础物理课程节选

Strong bonds means the material will resist and applied force.

强键意味着,材料能够承受外力。

麻省理工公开课 - 固态化学导论课程节选