答案　D　[考查虚拟语气。句意：要是我知道他们等我，我就会早点来了。题干中but I didn't know...用了过去时，表示过去的事实，主句应用表示与过去事实相反的虚拟语气，相当于 If I had known that they were waiting for me, I would have come sooner...。故选D项。]

　　2．________， we could not have finished the work on time.

　　A．If they do not help us

　　B．Was it not for their help

　　C．Should they offer to help us

　　D．But for their help

　　答案　D　[这里是含蓄虚拟语气用法。这句话的意思是：要不是他们帮忙，我们不会按时完成工作的。]

　　3．________today, he would get there by Friday.

　　A．Was he leaving

　　B．If he is leaving

　　C．Were he to leave

　　D．If he leaves

　　答案　C　[考查倒装虚拟语气。原来顺序是：If he were to leave today, 表示对将要发生动作的虚拟，用过去将来时。句意：如果他今天出发的话，那周五就应该到了。]

　　4．If only I________how to operate a computer as you do!

　　A．had known

　　B．would know

　　C．should know

　　D．knew

　　答案　D　[if only引导的句子，与wish用法一样，对现在的情况表示虚拟，用过去时。选D项。句意：要是我像你一样懂得怎样操作计算机就好了。]

【2017届高考英语（重庆专用）二轮精练：选修6 unit2 period 3】相关文章：

★ 2017届高考英语二轮复习课时训练：19（含解析）

★ 【人教版】2014届高考英语一轮复习指导考点针对练：选修6 unit5《The power of nature》

★ 2014高考英语（新人教版）一轮基础训练（3）A、B卷（附答案或解析）

★ 【浙江专用】2014届高考英语一轮复习课时作业(八)必修2Unit 3《Computers》

★ 【北京专用】2014届高考英语一轮复习方案课时作业：必修3 Unit 1 Festivals around the world

★ 【人教版】2014届高考英语一轮复习指导考点针对练：选修6 unit3《A healthy life》

★ 2017届高考英语二轮复习课时训练：9（含解析）

★ 2017届高考英语二轮复习书面表达限时测验：4（含解析）

★ 【北京专用】2014届高考英语一轮复习方案课时作业：选修7 Unit 3 Under the sea

★ 【人教版】2014届高考英语一轮复习指导考点针对练：选修7 unit1《Living well》