题目内容：

it may now be too late to clean up the river没怎么理解
having suffered such heavy pollution already ,it may now be too late to clean up the river
我认为it may now be too late to clean up the river应该被还原为
to clean up the river may now be too late 那么主语应该是to clean up the river 这句话就错误了
我想知道怎么看出逻辑主语是river
越详细越好,谢谢

优质解答

此问题术语分词的逻辑主语与分词独立结构可以这么理解（但不推崇）,把原句变为having suffered such heavy pollution already,river may now be too late to clean up.一般情况下,作状语的分词的逻辑主语就是句子的...