with tears dripping down his face and off his chin,the boy pointed to a spot
问题描述：
with tears dripping down his face and off his chin,the boy pointed to a spot
dripping 换成flowing,为何不可
答
简单来说drip down是一个及物型或不及物型（vt.&vi.)短语,flow down是一个不及物型(vi.)短语.eg.As riptide is rushing here,may flow down layer by layer and make waterfall thereby,it seems tigers are roaring...