66. turn one's back on sb. (=turn away from sb. in an impolite way)不理睬(某人)，背弃，抛弃
67. behind one's back背着某人(说坏话)
68. be based on / upon基于
69. on the basis of根据…，在…基础上
70. beat…at在…运动项目上打赢
