so的倒装问题

问题描述:

so的倒装问题
例如:So do i
那么so 的现在完成进行时如何表示?
so have been
那么过去进行时呢?
so was 那和过去式有何区别?

Jack was reading a book at that time.So was I.
Mary has finished her homework.So have I.
倒装句中用be动词或助动词