natural force

详细解释:【法】 自然力

例句：

The natural force of attraction exerted by a celestial body, such as Earth, upon objects at or near its surface, tending to draw them toward the center of the body.重力天体如地球，所施加的自然吸引力，如地球，对处于或接近其表面的物体有将它们拉向其中心的趋势