倒装高手请进Only when he had done it___that he had made a mistake.
问题描述：
倒装高手请进Only when he had done it___that he had made a mistake.
a.he had realized
b.had he realized
c.did he realize
d.he did realize
选择哪个?为什么?我水平太差请说详细一下,谢谢!
答
选C,only修饰副词,介词短语,状语从句置于句首,句子要部分倒装,尤其是在修饰状语从句时,状语从句不倒装,主句部分倒装,将助动词置于主语之前.因为he had done 在realize 动作之前发生,所以realize用过去是就行了