three rowadj.三行的threenum.三n.三；三个adj.三个的three-fold purpose三重意义three-layers frame三层结构three - represents三个代表three-contact plug三心塞子three-tip fluxgate三端式磁通门three conductor jack三芯塞孔three-button plate三钮板three-day sickness三日热three line array CCD三线阵CCDthree-mode designs三方式设计