backward pig发育不良的仔猪
backwardadj.向后的;落后的adv.向后
backward-curved-blade fan后向曲叶式风机
backward wave power amplifier回波功率放大器
backward stroke of the piston活塞回程
backward hierarchical pointer向后层次指针
Backward production capability落后产能
backward-wave tube amplifier返波管放大器
backward and forward extrusion正反挤压
backward differential equation后向差分方程