if条件状语从句中，虚拟语气下，if省略had可以提前的had是助动词还是实

if条件状语从句中，虚拟语气下，if省略had可以提前的had是助动词还是实

if引导条件状语句类及虚拟条件句判断 1、条件句两类： 1).真实条件句（Sentences of Real Condition）：凡假设情况发性能,真实条件句.例： ⑴、If I have time ,I will help you with this work.我间帮助做工作. ⑵、As long as I say anything wrong,you must point it out.要我说错,定要指. ⑶、If time permits,we'll go fishing together.(间,我起钓鱼.） 2).虚拟条件句（Sentences of Unreal Condition）：假设能实现,虚拟条件句.例： ⑴、If I were you ,I would have attended the meeting.我,参加议. ⑵、If he had 中国e here yesterday,he would have seen his old friend.假昨,看见朋友. ⑴、If it had rained yesterday,we would have stayed at home.（昨雨,我留家.） 2、.if条件状语句虚拟语气判断 判断真实条件句非真实条件句.非真实条件句才使用虚拟语气.通句意思,看假设条件否能够实现,能够实现真实条件句,能使用虚拟语气；假设条件能实现则非真实条件句,要用虚拟语气. 判断假设与哪事实相反.通三种情况：①与事实相反.②与现事实相反.③与事实能相反. 3、退步 退步指准确判断该句与哪事实相反,按虚拟语气退步处理句谓语词态.即：非真实条件状语句,谓语词按情况退步.： ①与事实相反,句用完形式表示. ②与现事实相反,句用般形式表示. ③与事实能相反,句用形式表示. 主句则用情态词would,should,could 等加与句致词形式.例： ⑴、If I had 中国e her yesterday,I would have seen him. ⑵、If I were a teacher,I would be strict with my students. ⑶、If it should snow tomorrow,they couldn't go out. 4、注意事项 ①if条件句were,should,had,省if,并使用倒装语序. ②现代英语if条件状与句谓语词be其形式般用were