The way to reduce the noise of the engine of the small four-wheeltractor is pointed out.
为小四轮拖拉机发动机的降噪指明了方向。
2
Therefore, the adjustment of small four-wheeltractor and trailer brakes simultaneously host should be to adjust the main trailer.
因此，调整小四轮拖拉机主机与挂车刹车同步时，应以调整挂车为主。
3
Paper introduces a technique of the normal four-wheeltractor equipped with exhaust gas controlling device and designs a computer safety monitor system.