threepennyadj.三便士的；无价值的；便宜的threenum.三n.三；三个adj.三个的three social structure theories三种社会结构理论three points measurement method三点法three - year college students专科生three-circle magnitute method三圆幅值法three-dimensional measurement三维测量Three Ancient Books about Rites三礼three-layers system structure三层体系结构Three types of cesarean section三种剖宫产术three-colour binocular sensor三色双眼传感器three-phase unbalanced degree三相不平衡度

1. I bought a basketball book for three yuan.
   我花了三元钱买了一本篮球书。
2. A dozen of stampes cost three bucks each, how many stampes are there?
   一打每张三元的邮票共有几张？