Only when I left home to go to college how much my mother had done for me.
A. did I realize
B. I realized
C. had I realized
D. I had realized
网友回答
(答案→)A. did I realize
B. I realized
C. had I realized
D. I had realized
解析:句意:只有当我离开家去上大学,我才意识到妈妈为我做了多少事情。这句话用only+时间状语从句,放在句首,后面的主句用部分倒装,助动词提前,因为realize这个动作,就是发生在when I left home to go to college,所以用一般过去时,所以选A。