Question

I have been to Beijing before. ______

A So do i B SO had i C SO have i D SO did I
请详细解答并分析错误的答案项。非常感谢

Answer 1

C
表示说话者也适用上述情况，用so + be/have/has/情态动词+主语
答句可转换成：I have been to Beijing before, too. 故用have
若此题改为：I had been to Beijing . 答句用SO had i (=I had been to Beijing, too.)
若此题改为：I went to Beijing . 答句用SO did i (=I went to Beijing, too.)

Answer 2

c
前面用的是现在时态 所以后面也要一致 用助动词have

Answer 3

D