three pair三对threenum.三n.三；三个adj.三个的three--line CCD scanners三线阵CCDThree-gorge hydrogenerator水轮发电机three-phase load unbalance三相负荷不平衡three-dimensional gas fire三维气体火灾Three main groups of islands三个主要的岛群three-quarter-turn stair三跑楼梯three phase dual speed motor三相双速电动机three layers of human nature人性的三个层面three-way emission control三元催化净化Three-level Categorization三层次说