he would have succeeded in the examinations. A. If he has worked hard, B. If he

题目考察if连接的条件句中的虚拟语气结构：

表示未来实现的可能性极小,if从句用“should /were to + do”，主句中“should /would / could / might to do”

例如：If I should/ were to so the experiment, I would do it some other way.

表示与现在事实相反，if从句用过去式，主句用“should / would / could /might + to do”

例如：If I had abike, I would lend it to you.

表示与过去事实相反，if从句用过去完成式，主句用“should / would / could/ might + to have done”

例如：If he hadbeen here, he would have helped you.

并注意，if从句中，若有were, had, should三词时，可省去if，同时采用主谓语倒装形式来表示条件。

例如：Shouldanyone call, please take a message.