Among these forces is the neglect of vertical forces, which is not too serious because they are quite small compared with the earth's gravitational attraction.
Among these forces is the neglect of vertical forces, which is not too serious because they are quite small compared with the earth's gravitational attraction.
在这些力中，垂直力受到忽视，但因为它们与地球的重力相比微不足道，所以这不是一个十分严重的问题。