refrigerator在这里不是指冰箱，而是指一个‘冷若冰霜的人’，当然多半是女人
所以a walking refrigerator实际上就是指这个人很冷
例句
Will you come to Martha's birthday party ?
Oh,I'd love to ,but she is a walking refrigerator,and well, most of cold woman are pretty.
I can't stand her.
类似还有a walking dictionary,a walking encylopedia即称赞一个人很有学问.
