主力军的英文：
main force
- Rural credit cooperatives have become the main force of rural financial service.
农村信用社已成为农村金融服务的主力军。 - The avxiliary unit is call in only when the main force have been overtax
只有在主力军承受过重压力时才会召来预备部队
adj. 主要的；全力的，尽力的
n. 总管道，总线；干线，电力网，电源；体力
- by (main) force
用蛮力, 全靠气力; 以最大的力气 - main gate lodge
大闸区；大闸门房；大闸传达室 - This is the main road into town.
这是进城的主要道路。 - This is the main traffic artery.
这条路是主要交通干道。 - The river has three main branches.
这条河有三条主要的支流。
n. 军队，暴力
v. 强迫，用力推动
- by (main) force
用蛮力, 全靠气力; 以最大的力气 - The force is spectacular!
这个瀑布很壮观！ - resultant force
合力 - The threat will force greater dispersion of their forces.
恫吓将迫使他们把兵力铺得更广。 - The tension force, shear forces (including pushing force, cutting force and friction force), impulse force, hydrodynamic drag on the suction pipes, and the force resulted from the pressure difference, etc, are the main forces for detail discussion in this paper.
详细讨论了主要作用力：在波浪补偿器作用下的缆绳拉力、耙头与海床间的土壤剪切力、作用在耙吸管上的水流阻力及由于压力差在耙头处产生的推动力等。