问题补充:
---Why didn’t you go to yesterday’s meeting?
---I would have but I too busy working on the important experiment.
A. had been
B. was
C. were
D. am
答案:
A. had been
(答案→)B. was
C. were
D. am
解析:根据前半句是I would have (gone to…),可知这里要表达的意思是:我本来是去的,但是…当时太忙了,所以确定用一般过去时.