only when I left my parents for Italy did i realize how much I loved them

问题描述:

only when I left my parents for Italy did i realize how much I loved them
这个句子中“did i realize"可以换成had i realized吗?为什么?这个句子的成分是什么?是my parents做主语吗?状语呢?

首先,不可以换,这是only后面的句子语序要倒装,而且主句是一般现在式,动词的助词是did 其次,when I left my parents for Italy 做时间状语,后面的是主句