n.脊梁骨,脊椎,分水岭,支柱,决心,毅力
Agriculture forms the backbone of the rural economy.
农业是农村经济的基础。
Petty officers are the backbone of a navy.
军士是海军的骨干。
The wounded soldiers showed much backbone before the enemy.
受伤的士兵在敌人面前表现出了威武不屈的精神.