When ____to compare the education systems of China and German,the professor gave no comment.a.asked him b.asked c.being asked d.asking him请问应该选哪个 请讲一下原因
问题描述：
When ____to compare the education systems of China and German,the professor gave no comment.
a.asked him b.asked c.being asked d.asking him
请问应该选哪个 请讲一下原因
答
When ____to compare the education systems of China and German,the professor gave no comment.
a. asked him b. asked c. being asked d. asking him
应该选B。 英语中和省略，一般是省去相同主语和be动词。所以，这句话可以理解成省略the professor was，即：When the professor was asked to compare the education systems of China and German......当教授被问及比较中德的教育*时，......
答
选B 因为 when 后面省略了he was ,这是把时间状语从句简化为过去分词短语作状语.语法是：句子并不是越复杂越好,如果在一个句子中有多个从句,会使人发晕,所以应尽量简洁,简单的方法之一就是把从句改为现在分词短语（...