Question

"If it ________ for the snow, we ________ the mountain yesterday．"

A. were not; could have climbed
B. were not; could climb
C. had not been; could have climbed
D. had not been; could climb

Answer 1

答案C
原题中的yesterday是信息词，可暗示该句应选与过去事实相反的虚拟语气条件与主句的动词形式。从句用过去完成时，而主句用could+have+过去分词。