The force of gravity makes things fall to earth.

引力使物体落向面。

It is gravitation that causes the apple to fall.

是吸引力使苹果下落。

The geotropism growth was a response of hypha to gravity and the geotropic sensitive was at the hyphal apex.

丛枝菌根真菌菌丝延伸生长部位是菌丝，其生长的向性是引力的应，应的敏部位也在生长菌丝的。

This dissertation presents the theory and method on the establishment of height datums.And some problems on the geocenter motion are also studied.

文系统研究了建立高程基准的理论与方法、运动规律及其高程基准的影响等有关问题。

Height is a measurement at right angles to this surface, and though gravity pulls mainly toward the centre of the earth, the geocentre, there are local variations.

高程是一个垂直于这个表面的测度，而虽然重力总是将物体向方向拉，但局部总会有一些变化。