He would have been a doctor 20 years ago, but he to be a teacher.
A. chooses
B. chose
C. had chosen
D. has chosen
网友回答
A. chooses
(答案→)B. chose
C. had chosen
D. has chosen
解析：考查虚拟语气和时态。But后面的句子要使用陈述语气，共计前半句的would have been说明本题是与过去相反的虚拟语气，故But后面要使用过去时。故B正确。