高中英语 Unit 21 Human Biology Section Ⅷ Grammar学案（含解析）北师大版选修7-北师大版高二选修7英语学案VIP专享

Section Ⅷ Grammar单元语法项目(一)——条件句和混合条件句 语法图解探究发现A．① If current Olympic champion Marion Jones took such drugs, she would probably have broken that world record more than once.②If Peter was a more skillful player, he would have scored more points.B．③ Ben Johnson would still be the 100 metres world record holder, if he had not been caught.④If he had broken that record, he would be a worldfamous runner now.[我的发现](1)A 组句子中，从句表示与现在事实相反的假设，而主句表示与过去事实相反的结果。由此可知混合条件句可以用来谈论“非真实的、常常是想象中的现在状态，可能对过去有影响”，其构成形式是：“if＋主语＋动词的过去式，主语＋would_have_done”。(2)B 组句子中，从句表示与过去事实相反的假设，而主句表示与现在事实相反的结果。由此可知混合条件句可以用来谈论“想象中的过去事件可能对现在有影响”，其构成形式是：“if＋主语＋had_done，主语＋would ＋动词原形 ”。在英语中，我们一般把条件句分为两种，即真实条件句和非真实条件句。非真实条件句亦可称为虚拟语气。虚拟语气表示说话人的愿望、假设、猜测或建议，而不表示客观存在的事实。一、if 条件状语从句中的虚拟语气主从句构成时态if 虚拟条件句主句与现在事实相反if＋主语＋动词过去式主语＋would/should/could/might＋动词原形与过去事实相反if＋主语＋had＋过去分词主语＋would/should/could/might＋have＋过去分词与将来事实相反if＋主语＋主语＋would/should/could/might＋动词原形If I were a bird, I could fly.如果我是一只鸟的话，我就能飞了。If we had started earlier, we would not have missed the train.如果我们早点出发，就不会错过这列火车了。If he shouldn't come tomorrow, we should put off the meeting till next Monday.要是他明天来不了，我们将把会议推迟到下周一。[即时演练 1] 用所给动词的适当形式填空①(2017·北京高考改编)If the new safety system had_been_put (put) to use, the accident would never have happened.②(湖南高考改编)Sorry, I am too busy now, if I had (have) time, I would certainly go for an out...