英语语法中的条件句
English Conditionals | English Grammar 英语语法中的条件句
Conditional Sentences: Rules You Need to Know 条件句:你需要知道的规则
Conditionals are sentences with two clauses, an “if” clause and a main clause, that are closely related. Generally, conditional sentences are often divided into different types. 条件句是由两个从句组成的句子，一个是if从句，另一个是main从句。一般来说，条件句通常分为不同的类型。
Types of Conditionals in English 英语条件句的类型
Zero Conditional 零条件
(Present Real Conditional) (现在的条件)
In general, “zero conditional” refers to conditional sentences that express a factual implication, rather than describing a hypothetical situation or potential future circumstance. The term is used particularly when both clauses are in the present tense, however such sentences can be formulated with a variety of tenses/moods, as appropriate to the situation. 一般来说，“零条件句”指的是表达事实含义的条件句，而不是描述假设的情况或潜在的未来情况。当两个从句都用现在时时，这个词就会被特别使用，然而这样的句子可以根据情况用不同的时态/语气表达。
How to use:We use the zero conditional to talk about things that are always true, like a scientific fact. 如何使用:我们用零条件来谈论那些总是正确的事情，比如科学事实。
For example:例如:
If you mix blue and red, you get purple. 如果你把蓝色和红色混在一起，就会得到紫色。If it rains, the grass gets wet. 如果下雨，草就会湿。If I go to bed early, I always get up very early. 如果我早睡，我总是起得很早。If you want to come, call me before 5:00. 如果你想来，5点前给我打电话。If I make a silly mistake, I laugh. 如果我犯了一个愚蠢的错误，我会笑。
First Conditional 第一个条件
(Present or Future Real Conditional)(现在或将来的真实条件)
“First conditional” refers to a pattern used in predictive conditional sentences, i.e. those that concern consequences of a probable future event. In the basic first conditional pattern, the condition is expressed using the present tense. In some common fixed expressions or in old-fashioned or excessively formal, the present subjunctive is occasionally found. The consequence using the future construction with “will” (or “shall”). “第一条件句”指的是预测条件句中使用的一种模式，即那些与将来可能发生的事件有关的句型。在基本的第一条件句型中，条件用现在时表示。在一些常见的固定表达中，或在老式的或过于正式的表达中，现在时虚拟语气偶尔会出现。使用“will”(或“shall”)将来构造的结果。
How to use: We use the first conditionalwhen we talk about possibilities in the present or in the future. 如何使用:当我们谈论现在或将来的可能性时，我们使用第一个条件句。
For example: 例如:
If need be, we’ll rent a car. 如果需要的话，我们会租一辆车。If I find her address, I’ll send her an invitation. 如果我找到她的地址，我就给她发个请帖。Elaine will buy the drinks if somebody helps her carry the bottles. 如果有人帮伊莱恩搬瓶子，她就会买饮料。
Second Conditional 第二个条件
(Present Unreal Conditional)(现在不真实条件)
It should be noted that the “second conditional” refers to a pattern used to describe hypothetical, typically counterfactual situations with a present or future time frame (for past time frames the third conditional is used). And, in the normal form of the second conditional, the condition clause is in the past tense (although it does not have past meaning. The consequence is expressed using the conditional construction with the auxiliary “would”. 应该指出的是，“第二个条件”指的是一种模式，用来描述假设的、典型的具有当前或未来时间框架的反事实情况(对于过去的时间框架，使用第三个条件)。而且，在第二条件句的正常形式中，条件从句是过去时(尽管它没有过去的意思)。结果用条件结构表示，辅以“would”。
How to use: The second conditional is used to talk about Imaginary situations in the present or future. 如何使用:第二个条件用于谈论现在或将来的假想情况。
For example: 例如:
If he had more time, he would learn karate. 如果他有更多的时间，他会学习空手道。She could win the prize if she practiced hard. 如果她努力练习，她会赢得奖品。
Third Conditional 第三个条件
(Past Unreal Conditional) (过去的不真实的条件)
Generally, “third conditional” is a pattern used to refer to hypothetical situations in a past time frame, generally counterfactual (or at least presented as counterfactual). Here the condition clause is in the past perfect, and the consequence is expressed using the conditional perfect.一般来说，“第三个条件”是指过去一段时间内的假设情况，通常是反事实的(或至少以反事实的形式出现)。这里条件从句是过去完成时，结果用条件完成时表示。
How to use: We use thethird conditional when we talk about Imagine situations in the past. 如何使用:当我们谈论过去的情景时，我们使用第三个条件句。
For example: 例如:
If she had studied hard last week, she could have passed the exam. 如果她上周努力学习，她就能通过考试。I would have written you a postcard if I had had your address. 如果我知道你的地址，我就会给你写张明信片。
Mixed Conditionals 混合条件
It should be noted that “mixedconditional” usually refers to a mixture of the second and third conditionals (the counterfactual patterns). Here either the condition or the consequence, but not both, has a past time reference. 应该指出的是，“混合条件”通常指的是第二和第三条件条件(反事实模式)的混合。这里的条件或结果，但不是两者都有一个过去的时间参考。
Mixed 1 Conditional 混合1条件
(Present result of a past condition)（过去条件的现在结果）
When the condition refers to the past, but the consequence to the present, the condition clause is in the past perfect (as with the third conditional), while the main clause is in the conditional mood as in the second conditional (i.e. simple conditional or conditional progressive, but not conditional perfect). 当条件指的是过去时，但指的是现在的结果时，条件从句是过去完成时(如第三个条件句)，主句是条件语气，如第二个条件句(如简单条件句或条件进行时，但不是条件完成时)。
How to use: Present result of a past condition. 如何使用:过去情况的现在结果。
For example: 例如:
If she hadn’t stayed up late last night, she wouldn’t be so tired now. 要不是她昨晚熬夜，她现在就不会这么累了。If he had worked harder at school, he would be a student now. 如果他在学校学习更努力的话，他现在就会是一个学生了。Mixed 2 Conditional 混合2条件
(Past result of a present or continuing condition) (目前或持续状态的过去结果)
When the consequence refers to the past, but the condition is not expressed as being limited to the past, the condition clause is expressed as in the second conditional (past, but not past perfect), while the main clause is in the conditional perfect as in the third conditional. 当结果指过去时，但条件不表示为限定于过去时，条件从句表示为第二条件句(过去，但不是过去完成时)，而主句表示为条件完成时(第三条件句)。
How to use: Past result of a present or continuing condition. 使用方法:当前或持续状态的过去结果。
For example: 例如:
If I were you, I would have learned English earlier. 如果我是你，我早就学会英语了。
How to Use Unless in English 如何使用除非在英语
Unless means if not. We use unless in conditional sentences instead of if not. 除非意味着如果不是。我们在条件句中使用unless而不是if not。
How to Use Wish in English 英语中如何使用Wish
Learn How to Use Wish in English. 学习如何在英语中使用Wish。
When we want to express a wish/desire in English for a situation to be different to what it actually is then it is very common to use the verb “to wish”. 当我们想用英语表达一种愿望/愿望，希望一种情况与实际情况不同时，使用动词“to wish”是很常见的。
English Conditionals in One Table 英语条件句在一张表中