if it for the snow we the moutain yesterdayIf it __________for the snow,we ___________the mountain yesterday.A.were not; could have climbed B.were not; could climbC.had not been; could have climbed D.had not been; could climb选C为什么

if it for the snow we the moutain yesterdayIf it __________for the snow,we ___________the mountain yesterday.A.were not; could have climbed B.were not; could climbC.had not been; could have climbed D.had not been; could climb选C为什么
if it for the snow we the moutain yesterday
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
选C为什么

if it for the snow we the moutain yesterdayIf it __________for the snow,we ___________the mountain yesterday.A.were not; could have climbed B.were not; could climbC.had not been; could have climbed D.had not been; could climb选C为什么
这是虚拟语气,此句表示与过去事实相反的假设,条件从句中用“had (not) +过去分词”形式,主句中的动词用“could/would/should+have+过去分词”的形式.这句话的意思是：如果昨天不是因为下雪,我们就能爬山了.而事实是昨天下雪了,没有爬山,这句话是对过去事实相反的假设,用虚拟语气.所以选C.

C. had not been; could have climbed

假设过去的，主句用完成是，从句退一步用过去完成时