今天2015SAT语法材料之虚拟语气的内容，通过实例进行具体分析，将做题方法应用到具体情况中去分析，相信你的成绩就会有所提高的!
我们今天主要从以下两个方面来认识SAT中的虚拟语气
1.虚拟语气的形式
2.倒装虚拟
英语中的语气主要有以下三种
1. 陈述语气
2. 祈使语气
3. 虚拟语气
简单来说，虚拟语气是相当于if条件句的内容不可能实现， 或实现的可能性很小的时候，要对if条件句和主句的动词形式进行适当变化
1. if 从句表达的意思和现在的情况相反或目前不可能实现
If I had time, I would go now.
If 条件句：did, 主句：would+do
值得注意的是，be动词在虚拟语气中必须用were, 不论其原来 的形式是is , am 还是are.
If I were a bird, I would fly.
2. if 从句所表达的意见与过去事实相反
例句1：If I had married you, you would have been the president.
If 条件句：had done, 主句：would+have done
例句2：:If china had not implanted the policy of “reform and opening to the outside”,in would not have been so prosperous.
3. If条件句的内容与将来事实相反或将来实现的可能性很小
If I should/were to win a lottery of 10 million dollars, I would buy you a big house.
If 条件句：should/were to 主句： would+do
4. 倒装虚拟
在if 条件句中含有should, had, were 时，常常会把if省去，并将shoud,had, were 放在句首(其余部分顺序不变)，这样就构成了文法上的”倒装虚拟句”。这种句子出了形式不同外，和正常的虚拟句的功能是完全一样的。
例句1： If I were you, I would go.
倒装虚拟句： Were I you, I would go.
例句2：If I should win a lottery, I would take a vacation in Europe.
倒装虚拟句：Should I win a lottery, I would take a vacation in Europe.
例句3：If you had come here earlier, we would have finished the job now.
倒装虚拟句：Had you come here earlier, we would have finished the job now.
例题1：If there had been a power failure, the hospital will run on electricity from its own generator, which can operate for 200 hours.
(A) If there had been
(B) If there were
(C) Had there been
(D) Should there be
(E) There had been
答案：D
分析：主句是对将来情况的虚拟，所以从句的形式应该是“if+主语+should+动词原形” 选项中只有D选项是这种形式的倒装形式。
例题2： He was convinced that if property taxes would have rose any higher, he would have had
to move a different area.
(A) if property taxes would have rose
(B) if property taxes would rise
(C) if property taxes had risen
(D) had property taxes rose
(E) were property taxes to rise
答案: C
分析： 句中用的是would have had的形式，那么if条件句中的对应形式应该是过去完成时的形式，所以选择C选项。
例题3： By painting them this afternoon, the walls would be completely dry by tomorrow evening.
(A) By painting them
(B) If they would have been painted
(C) Were they to be painted
(D) After painting them
(E) They would be painted.
答案：C
分析：根据主句判断，这个句子是对将来的虚拟，所以C选项是对将来虚拟的倒装形式。
上面就是今天网小编给大家带来的2015SAT语法材料之虚拟语气的内容，建议大家将题目收入自己的笔记之中，方便以后再次复习。