我举两个例子:①动名词的复合结构:I never heard of a person of character doing such a thing.②现在分词作宾语补足语:I saw a young mother slapping her child.可是这两个的语法是怎么判断的呢?就是说,是怎么判断这是动名词的复合结构而不是现在分词作宾补呢?