if的条件句的三种用法
if与will怎么用？
if与will怎么用？
if后加一般现在时,will后加一般将来时 ，例如:
If it rains,we will not go to shool.
当will不表将来时态，而是个情态动词“愿意”的意思时。
如：
If you will go， please tell me.
如果你愿意去的话，请告诉我。
. 还有if不是如果的意思，也就是说引导名词从句时，也可以的。
如：
I dont know if he will come back tonight.
if引导条件状语从句的三种时态？
if引导的虚拟条件句，
1. 过去的时间，谓语动词是：had 过去分词
2. 将来的时间，谓语动词是：
be用were ；were to do something；实义动词用过去式
3. 现在的时间，谓语动词be用were； 实义动词用过去式
1. If you had come here earlier, you would have met him.
2.If it were to rain tomorrow, we would not go to the countryside.
3. If you were here now, you would have a talk with him face to face.
if开头的句子是什么类型？
If引导的条件状语从句，从句用一般现在时态，主句用将来时态
If it is fine tomorrow I will go to the park.
◎if 引导的虚拟语气
1.与现在事实相反：从句用过去时态（be动词一律用were）主句用would 动词原形
If you knew everything,you would not be so angry with him.
If i were you I would not be confident
2.与过去事实相反：从句用过去完成时，主句用would 现在完成时
If I had known his telephone number,I would have telephoned him