Conditional Sentences

Conditional Sentences
Grammarly
Grammar

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  There are four types of conditional sentences.
  
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  It’s important to use the correct structure for each of these different conditional sentences because they express varying meanings.
  
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  Pay attention to verb tense when using different conditional modes.
  
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  Use a comma after the if-clause when the if-clause precedes the main clause.
  

Conditional sentences are statements discussing known factors or hypothetical situations and their consequences. Complete conditional sentences contain a conditional clause (often referred to as the if-clause) and the consequence. Consider the following sentences:
If a certain condition is true, then a particular result happens.
I would travel around the world if I won the lottery.
When water reaches 100 degrees, it boils.
What Are the Different Types of Conditional Sentences?
There are four different types of conditional sentences in English. Each expresses a different degree of probability that a situation will occur or would have occurred under certain circumstances.

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  Zero Conditional Sentences
  
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  First Conditional Sentences
  
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  Second Conditional Sentences
  
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  Third Conditional Sentences
  

Let’s look at each of these different types of conditional sentences in more detail.
How to Use Zero Conditional Sentences
Zero conditional sentences express general truths—situations in which one thing always causes another. When you use a zero conditional, you’re talking about a general truth rather than a specific instance of something. Consider the following examples:
If you don’t brush your teeth, you get cavities.
When people smoke cigarettes, their health suffers.
There are a couple of things to take note of in the above sentences in which the zero conditional is used. First, when using the zero conditional, the correct tense to use in both clauses is the simple present tense. A common mistake is to use the simple future tense.
When people smoke cigarettes, their health will suffer .
Secondly, notice that the words if and when can be used interchangeably in these zero conditional sentences. This is because the outcome will always be the same, so it doesn’t matter “if” or “when” it happens.