—Did you notice John was not at work today?—No.If working I would have noticed it.A. I’dB

问题补充：

—Did you notice John was not at work today?

—No.If working,I would have noticed it.

A. I’d

B. I was

C. I’d been

D. I were

答案：

A. I’d

B. I was

(答案→)C. I’d been

D. I were

解析：从“Did you notice” 可知下面的回答是针对过去情况的假设，用过去完成时，即I’d been相当于I had been。