traction of pelvis along the longitudinal axis

例句：

1. 1.The car's engine has a strong traction on the road.
   汽车的引擎在路面上有很强的牵引力。
2. 2. The train needs more traction to move faster.
   火车需要更多的牵引力才能更快地移动。
3. 3. The heavy load is causing the truck to lose its traction.
   沉重的负载使得卡车失去了牵引力。