If you firm action to deal with it at once you wouldn’t suffer heavy losses tomorrow.A.

问题补充：

If you firm action to deal with it at once, you wouldn’t suffer heavy losses tomorrow.

A. take

B. took

C. has taken

D. had taken

答案：

A. take

(答案→)B. took

C. has taken

D. had taken

解析：考查if的非真实条件句：句意：如果你立刻采取有力的行动解决它，明天你就不会遭受严重的损失了。主句是和将来相反，用would do表示虚拟，if条件句是和现在相反用过去时，表示虚拟，选B。