three pads三支撑掌threenum.三n.三；三个adj.三个的three-focus objective lens三焦点物镜three-pit system of liming三槽浸灰法three.- dimension design三维设计three dimensional flow field三维流场three thousand and forty six(=3046) 三千零四十六Three phase four wire couper三相四线耦合器three large economic regions三大经济圈Three-dimensional focusing三维聚焦three-step distance relays三段距离继电保护装置three-dimensional template立体样板