高职高专实用英语教程-unit-4-Part-Ⅳ-Grammar完整版

1、 1. if 引导的虚拟条件句引导的虚拟条件句 与与现在现在事实相反事实相反 与与过去过去事实相反事实相反 与与将来将来事实可能相反事实可能相反 if虚拟条件句虚拟条件句 did （be动词用动词用were) would( should / might / could )动原动原 If I had a great deal of money now, I would buy a big house for my parents. 与与现在现在事实相反事实相反 If I were the schoolmaster , I would let the students get up a littl

2、e later. 与与现在现在事实相反事实相反 schoolmaster if虚拟条件句虚拟条件句 1、did 2、were to+ 动原动原 3、should +动原动原 would ( should / might / could ) 动原动原 If I met Obama some day, I would shake hands with him. If I were to meet Obama some day, If I should meet Obama some day, 与与将来将来事实相反事实相反 if虚拟条件句虚拟条件句 had +done would ( should

3、/ might / could ) have done If the boy had driven more carefully, he would not have caused the car accident. 与与过去过去事实相反事实相反 If the foreigner had learnt how to swim, he would not have been trapped on the island for four years. 与与过去过去事实相反事实相反 1、If+主语主语+动词过去式动词过去式 2、If+主语主语+were to+ 动词动词 原形原形 3、If+主语主语

4、+should +动词原动词原 形形 If+主语主语+ 动词的过去式动词的过去式 （be动词一般用动词一般用were) 主语主语+would ( should / might / could )动词动词 原形原形 即：即：If+一般过去时态一般过去时态 （be动词一般用动词一般用were) If+主语主语+had +动词的过动词的过 去分词去分词 即：即：If+过去完成时态过去完成时态 主语主语 + would ( should / might / could )have done 主语主语+would ( should / might / could )动词动词 原形原形 2.虚拟条件句中的

5、倒装虚拟条件句中的倒装 a.在虚拟条件句中，如果条件句中有在虚拟条件句中，如果条件句中有 were, had（助动词）或（助动词）或should时时，可，可 使用倒装结构，使用倒装结构， were, had,或或should 可可 提前提前，if省略省略。 b.若条件从句为否定句，否定词若条件从句为否定句，否定词not应应 置于主语之后，而置于主语之后，而不能与不能与were，should， had等缩略成等缩略成werent，shouldnt， hadnt置于句首置于句首。 1). If I had seen him then, I would have been very happy. = Had I seen him then, I would have been very happy. 2). If I should have time, I would go with you. = Should I have time, I would go with you. 3). If I were not so busy, I would go with