题目内容：

请问All buses ((having been canceled)) because of the heavy snow,they had to to there on foot.
All buses ((having been canceled)) because of the heavy snow,they had to to there on foot.
括号里的((having been canceled))能不能替换为canceled
我还问问,从句中动词的被动形式可以与动词的名词形式一样用,而不需要加be动词吗?

优质解答

可以替换为canceled,替换后,时间的先后关系就没有这么强烈的,更侧重于原因,即由于所有的公车被取消了,使得他们.
动词的被动形式都离不开be,因此动名词的被动形式中的be不能省.