1.辨别if 引导真实条件句和if引导的虚拟条件句的区别
If he has time, he will go with us.= Probably he has time and will go with us.
If he had time, he would go with us.=But in fact he has no time.
2.虚拟条件句中主句和从句的谓与动词构成形式如下表
if条件句中的谓与动词 主句的谓与动词
与现在的事实相反
might
3.混合时间的虚拟语气
如果条件句中的动作和主句的动作不是同时发生，主句和从句的谓语动词的形式应分别根据各自所表示的时间加以调整。
1)0If I had received the passport yesterday, I would start today.
2)If he had telephoned me last night, I would see him now.
3)If he had followed the doctor’s advice, he would be all right now.
4)If China had not been liberated, the working people would still be leading a miserable life.
