Question

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

Answer 1

B

试题分析：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。
点评：虚拟语气在条件句中的用法是：虚拟条件句与现在事实相反的假设，从句是If+主语+动词的过去式（动词be用were)，主句是：主语+should,would, might,could＋动词原形；与过去相反的假设从句用：If+主语+had +过去分词，主句是：主语＋should, would, might, could ＋have done；与将来相反的假设，从句用1、If+主语+动词过去式，主语＋should, would  do，2、If+主语+were to+ 动词原形，加主句3、If+主语+should +动词原形，加上主句的might, could＋动词原形