He busy yesterday, or he you with your experiment.
A. was; had helped
B. was; would have helped
C. had been; would have helped
D. were; would have helped
网友回答
A. was; had helped
(答案→)B. was; would have helped
C. had been; would have helped
D. were; would have helped
解析：考查时态和虚拟语气：句意：昨天他很忙，否则，他就可以帮助你做实验了。第一空是过去的事实，用一般过去式，这里or相当于if he hadn’t been busy这样的虚拟语气条件句，所以后面的主句用would have helped。选B。