题目内容：

what great difficulty they had making a living in old days!为什么这里用making而不用made?

优质解答

这是一个感叹句式.
首先让我们将它还原为陈述句：They had great difficulty making a living in old days.
这样再看看这个句子,是否找出了结构——have difficluty (in) doing sth.
好了,答案出来啦.因为省去了介词 in,而且感叹句语序与陈述句语序不同,所以难得一样看出来.