there yesterday, I could have asked him not to do so．
A. If I were
B. If I was
C. Had I been
D. Was I
网友回答
A. If I were
B. If I was
(答案→)C. Had I been
D. Was I
解析：考查含有if条件状语从句的虚拟语气。根据yesterday,可知指的是过去的情况，应该用if I had been there yesterday,可以将助动词had提到句首，省略if，即Had I been there yesterday。所以选C。