if后面的时态怎么用
当“if”作“如果、假如”讲,引导条件状语从句时,常常用一般将来时态与之搭配。
如 If it rains tomorrow, we will stay at home. If he doesnt come on time, Ill go myself.
当“if”作“是否”讲,引导宾语从句时,其具体时态要和主句一致。
一.if引导的条件状语从句中用一般现在时态。引导条件状语从句,用一般现在时代替将来时。
二.if后可以接虚拟语气。
(1)第一种是与现在事实相反,if从句谓语用过去式或者were。
(2)第二种是与过去事情相反,if从句谓语用过去完成时had+过去分词。
(3)第三种是与将来事实相反,if从句谓语用动词过去式,should +动词原形,或were to+动词原形。
三.if双语例句
1.She gets very upset if I exclude her from anything
要是有什么事情我不让她参加,她会非常难过。
2.He asked if I had left with you, and I said no
他问我是否和你一块儿离开的,我说不是。
3.Sometimes, that standard is quite difficult, if not impossible, to achieve
有时即便有可能达到那个标准,那也是非常困难。
4.If I could just make another small point about the weightlifters in the Olympics
请允许我就有关奥运会举重运动员的问题再补充一点。
5.I wonder if you\'d be kind enough to give us some information, please?
请问您能不能给我们提供一些信息?