条件句的几种正确分类

条件句也被称为if从句

一般来说，条件句分为两个部分：主句 + if引导的条件分句。

Zero conditional

用法

“zero conditional”指的是用于表达事实的条件句。在这种条件句中，没有假设的情况or潜在的未来可能，只有现在真实的条件。“zero conditional”常常用来表达科学事实。

结构

if + 一般现在时，.....一般现在时。（主句，if句全部使用一般现在时）

举例

If you mix blue and red, you get purple. 

If it rains, the grass gets wet.

If I go to bed early, I always get up very early.

First conditional

用法

“first conditional”指的是用来预测的条件句，在这种条件句中，条件是现在或将来真实存在的条件，“first conditional”通常用来表示现在或将来可能发生的事情。

结构

if + 一般现在时，.....一般将来时。（主句使用一般将来时，if句使用一般现在时）

举例

If I find her address, I'll send her an invitation.

Elaine will buy the drinks if somebody helps her carry the bottles.

Second Conditional

用法

“second conditional”通常用来描述假设的情况，这种条件句中，条件一般与现在或将来的事实相反。“second conditional”用来表示虚拟、假设的情况。

结构

if + 一般过去时，.... would/wouldn't do

举例

If I won a million dollars, I would buy a new car.

If I were you, I would quit smoking.

They would stay longer if they had more time.

Third Conditional

用法

“third conditional”同“second conditional”类似，用来描述假设的情况，但是在“third conditional”中，条件是与过去事实相反的。这种条件句通常用来表示假设过去的情况。

结构

if + 过去完成时，.... would/wouldn't have done（过去将来完成时）

举例

If I had got a gold medal, I would have been happy.

If the weather had been good, we would have gone picnic.

If she had studied hard last week, she could have passed the exam.