web前端超出两行用省略号表示的实现方法

span class="GW_bod0112211">
 吐鲁番特级无炳黑加仑葡萄干500g包邮无籽吐鲁番特级无炳黑加仑葡萄干500g包邮无籽吐鲁番特级无炳黑加仑葡萄干500g包邮无籽，超大孕妇零食
/span>

span{
  height: 40px;
  line-height: 20px;
  width: 300px;
  display: -webkit-box;
  -webkit-line-clamp:2;
  -webkit-box-orient: vertical;
  text-overflow: ellipsis;
  overflow: hidden;
}