请解释这个句子中long ago的用法:Stone does not decay, and so the tools of long ago have remained when even the bones of the men who made them have disappeared without trace. 句子选自《新概念英语》4册第一课
... was careless of John to break up the cup.该网友引用章振邦《新编英语语法》对这个句子的解释,说这里有两点值得注意:第一,不能把句中的 it与表示形式主语的 it 等量齐观,就是说,不能把 It was careless of John to break up the cup.这样的...