英语if的用法总结

if是英语学习中最为常见的介词之一，那么接下来一起去学习下if的相关用法吧！

用法

1、if作为连词，引导条件状语从句，表示假如，如果等。在复合句中如果主句用将来时，则if引导的状语从句用一般现在时。

例句：If it rains(从句)，I will stay at home（主句）=I will stay at home if it rains.如果下雨，我会待在家里。

He will come if you invite him.如果你请他，他会来的。

2、主句含有情态动词（must、may、canetc.）从句为一般现在时

例句：If you drive too fast，you may have an accident.=You may have an accident if you drive too fast.如果你开的太快，你很有可能会发生事故。

3、主句为祈使句,从句要用一般现在时态

例句：Don't play computer games if you don't finish your homework.不要玩电脑游戏除非你完成了家庭作业。

4、if于句首时中间用逗号隔开，主句后不用逗号

5、if可用unless(除非...)替换，unless=if...not...

6、用于虚拟语气，主句和从句都为一般过去式

例句：If you were a bird,you could fly.假使你是只鸟，你便会飞了。

7、if可引导让步状语从句，这时if有即使是，虽说的含义

例句：If I am wrong,you are wrong too.即使我说错了，那么你也不对。

以下是我为大家整理的if句型的用法 总结 ，希望能帮助大家更好地认识if句型，提高英语水平。 if的意思和用法： conj.如果，倘若; 即使; 〈口〉是否; 假设; n.条件，设想; 1. (表示条件)如果 ,主句用将来时，if从句用现在时表示将来 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 1)时态：可以表示过去，现在和将来的情况。它的基本特点是时态退后。 a. 同现在事实相反的假设。 句型 ： 条件从句主句 一般过去时should( would) +动词原形 If they were here, they would help you. b. 表示于过去事实相反的假设。 句型： 条件从句主句 过去完成时should(would) have+ 过去分词 The rice would not have been burnt if you had been more careful. If she had worked harder, she would have succeeded. If my lawyer had been here last Saturday, he would have prevented me from going. If he had come yesterday, I should / would have told him about it. 含义：He did not come yesterday, so I did not tell him about it. If he had not been ill and missed many classes, he would have made greater progress. 含义： He was ill and missed many lessons, so he did not make greater progress. c. 表示对将来的假想 句型： 条件从句主句 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 were to succeed, everything would be all right. If you should succeed, everything would be all right. 3. 是否 = whether 连接宾语从句 I wonder if she is ill. 不知她是否病了。 连接词 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. 我一感到有疑问就随时询问。 if作为连词的时候，一般用于条件状语从句或者是宾语从句或让步状语从句 if引导的条件状语从句：If he comes, please tell me.(如果，假如) 主句和从句位置可以互换，时态：主将从现 变成：Please tell me,if he comes. 宾语从句中：I want to know if(是否) he comes. 可改成：I want to know whether he comes. 当 句子 中有or not是 只能用whether——I want to know whether he comes or not. if句型的时态： 1.主过从过 2.主句一般现在时，从句任何时 3.客观真理用一般现在时 让步状语从句中，if 解释为即使 名词 cn. 条件;设想 There are too many ifs in his offer. 他的提议中条件太多了--------------------------------------------------------------------------------------if的用法相关 文章 ： 1. whether 和 if 用法总结归纳 2. graduate的用法说明 3. practise 的用法详解 4. quantity的语法和用法 5. discussion 的四点用法详解 6. mind的用法 7. refuse/ reject的用法区别 ​