物体的加速度与所受的合外力成正比，与物体的质量成反比。加速度的方向与合力的方向相同。
The alternation of motion is ever proportional to the motive force impressed; and is made in the direction of the right line in which that force is impressed.
The truth is, everyone is going to hurt you. You just got to find the ones worth suffering for.
农业创新不仅仅是技术问题，更是思维方式的转变。
Every great and deep difficulty bears in itself its own solution. It forces us to change our thinking in order to find it.