短语词组短语depth of tariff cut [税收]关税削减幅度radial depth of cut 径向切削深度limit depth of cut 界限切削深度optimum depth of cut 最佳挖掘深度Depth of cut notching 深切凹口critical depth of cut 临界切削深度depth of the cut 割口角度 返回 depth of cut