—Is your father a teacher?—Well he .A. used toB. was used toC. used to beD. is used to be

问题补充：

—Is your father a teacher?

—Well, he .

A. used to

B. was used to

C. used to be

D. is used to be

答案：

A. used to

B. was used to

(答案→)C. used to be

D. is used to be

解析：考查情景交际和used to的用法。“你爸爸是老师吗？”“嗯，以前是。”答语的言外之意是现在不是老师了。used to do sth.“过去常常做某事”；be used to do sth.“被用来做某事”；used to be中的be不能省略。故选C。