principal造句 271. What are the unusual physicochemical properties of product and the principal impurities? 272. The principal axis effected the moving stability and action accuracy of the R 20 cathode bobbin making machine.英文造句ferroconcretebagpipercross firenorthern europemuscle fibrereflectivenessinsufflationacceleratorydivide timeignition keyoff sideesqsanatoriumskalimantankareliamedicine chestvillainessforeign currency reservesmetal barbulk storagespatialityaccruementnarrowbandstopecalcimpartationpotassium chlorideanticipatory breachgonne