Question

英语if语法

英语if语法？！
就是IF后面如果加动词要什么形态？
还有其他的一些用法是什么？

Answer 1

if 引导的从句较多，个人以为一般状语从句较简单，而虚拟语气比较复杂，所以简单写了点虚拟语气用法。
if 虚拟用法
1、对将来虚拟 if +did/were to /should , ....would/could /might +do
其中 were to 和should 可以倒装
例如：If it were to rain = Were it to rain
If it should rain =should it rain
2、对过去虚拟if + had done,.....would + have done
倒装 Had it done .....
例外： If i had followed his advice ,i would not be in such trouble .句中用be 而非 done是因为现在处于困境中
3、对现在虚拟 if +did ,...would /could /might +do

Answer 2

conj.

1. (表示条件)如果

He will come if you invite him.

如果你请他,他会来的。

2. (表示虚拟)假如,要是

If I were you, I would never do that.

如果我是你,我决不做那件事。

3. (表示让步)即使

We'll go even if it rains.

即使下雨我们也要去。

4. 是否

I wonder if she is ill.

不知她是否病了。

5. (表示因果关系)每一次...的时候(总是会)

If I feel any doubt, I inquire.

我一觉得有疑问就发问。

n.

1. 条件;设想[C]

There are too many ifs in his offer.

他的提议中条件太多了。

Answer 3

if引导条件状语从句，主句可以是将来时，祈使句，或用情态动词引导的句子，从句可以是一般现在时。

Answer 4

最重要的就是if后面不能够跟将来时，都是用一般时来表示将来时。