（1）So do I
Mary went to a film yesterday. So did I.
玛丽昨天去看电影了。我也去了。（So do I表示肯定的替换，指玛丽做的事，我也做了。）
【分析】我们要注意其中的谓语，助动词、系动词、情态动词都是可以使用的，但结构不变。So的含义是also, too, in the same way.
The first box was empty. So was the second. （be是系动词。）
She can sing this song. So can I.（can是情态动词。）
He doesn't like fish. Neither do I.
（2）So I do
-I know you work hard. -So I do.
-He didn't go there. -No, he didn't.
（3）I do so
-He told me to come before 5. -I did so.
他告诉我5点前来到，我照做了。（I do so是正装结构，do可以是think, hope, believe, tell, expect等词。）
-Do you want to have a talk with her?
-I hope so.
-I hope not to.
（4）So it is with me
在这四种结构中，本结构最为复杂。So it is with me相当于It is the same with me。
-He is tired and stays at home.
-So it is with me.（So it is with me代替上句中be和stay这两种情况。）
Mary likes swimming, but doesn't like fishing. So it is with Dick.
玛丽喜欢游泳，但喜欢钓鱼。迪克也是这样。（So it is with同时代替肯定和否定两种情况。）
Marx was born in Germany and Genman was his native language. So is was with Engels.
Rose has made her study plan, but her brother hasn't. So it is with Mary and her brother. 罗斯做了学习计划，哥哥却没有做。 玛丽也做了学习计划，她哥哥没做。
In Yap Yap, only the rich have freedom of speech. So is was with old China.