He busy yesterday or heyou with your experiment.A. was;had helpedB. was;would have helpedC

问题补充：

He busy yesterday,or heyou with your experiment.

A. was;had helped

B. was;would have helped

C. had been;would have helped

D. were;would have helped

答案：

A. was;had helped

(答案→)B. was;would have helped

C. had been;would have helped

D. were;would have helped

解析：该题根据交际情景考查时态的用法。第一句有明确的时间状语yesterday，故用过去时。后一句表示过去的动作并没有发生，故用“would have done”。