人教版高一英语必背知识点总结梳理 篇14

　　一般过去时 should+ 动词原形

　　were+ 不定式 would + 动词原形

　　should+ 动词原形

　　If you succeeded, everything would be all right.

　　If you should succeed, everything would be all right.

　　If you were to succeed, everything would be all right.

　　混合条件句

　　主句与从句的动作发生在不同的时间，这时主，从句谓语动词的虚拟语气形式因时间不同而不同，这叫做混合条件句。

　　If you had asked him yesterday, you would know what to do now.

　　(从句与过去事实相反，主句与现在事实相反。)

　　If it had rained last night (过去), it would be very cold today (现在).