What Are Conditional Sentences? A Closer Look at a Common Writing Technique

Most English writers use conditional sentences in their writing without even knowing it. Learn “what are conditional sentences?” and how to use them properly. 

If you have ever written a statement with a dependent clause starting with the word “if,” then you have likely written a conditional sentence. 

Conditional sentences provide a foundation for making hypothetical situations or presenting conditions for action. They are similar to an if/then statement but without the word “then.”

These sentences use two clauses and different verb tenses to give a particular meaning, and understanding them will make your writing stronger or help with inferring the right information from sentences when you read this sentence type.

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What Are Conditional Sentences?

A conditional sentence is a sentence that has a conditional statement, usually in the form of “if,” followed by a result. It has two parts: the if-clause and the main clause. These two parts have a direct correlation to each other.

The Breakdown of a Conditional Sentence

To better understand this structure, take a moment to consider the two parts of a conditional sentence.

The first part is the if clause. This dependent clause often comes at the front of a conditional sentence, but it can come at the end as well.

The second part is the main clause. This independent clause states the result of the condition. If the action in the if-clause occurs, then the action in the main clause will or will likely occur.

4 Types of Conditional Sentences

There are four types of conditional sentences you could use in English writing. They are different in the amount of probability they indicate that the situation will or will not occur. These types range from a sentence that indicates something is going to occur to something completely farfetched. The four types of conditional sentences are:

• Zero conditional sentences
• First conditional sentences
• Second conditional sentences
• Third conditional sentences

Understanding each of these requires looking more closely at them, along with examples of them, to get a feel for how they are used.

Zero Conditional Sentences

Zero conditional sentences state general truths about a situation or scenario. These situations always occur together or always cause another action to happen. They have no or few exceptions.

These sentences follow this format:

• If + simple present, simple present.

Here is an example:

• If you eat more calories than you burn through exercise, you gain weight.

The zero conditional uses the simple present tense of the verb, and no other tense is acceptable. It also uses “if” or “when” as the conditional clause opener. You can use these two words interchangeably in this type of conditional sentence.

Here are additional examples:

• If the weather looks like rain, I take an umbrella with me.
• If I wake up early, I take time to read before starting my day.

First Conditional Sentences

The purpose of a first conditional sentence is to describe possible scenarios. First conditional sentences state an outcome that is likely to happen. However, the outcome is not guaranteed.

These sentences follow this pattern:

• If + simple present, will + base verb.

Here is an example:

• If you exercise to burn additional calories and don’t change your eating habits, you will lose weight.

It is incorrect to use the future tense in the if-clause, as in:

• If you will exercise to burn additional calories and don’t change your eating habits, you will lose weight. (incorrect verb tense)

Here are some additional examples:

• If it rains, I will need to wait before I leave.
• If the weather holds, we will play another inning.

Second Conditional Sentences

Sometimes in English grammar, we want to state something unlikely to happen. For instance, you likely will not win the lottery, but you might enjoy thinking about what you would do if you did. Second conditional sentences work in these hypothetical scenarios.

These sentences follow this pattern:

• If + simple past, modal + base verb.

Here is an example:

• If I won the lottery, I would buy a mansion on a beach.

 A common mistake is to use the present tense in the conditional clause, as in:

• If I win the lottery, I would buy a mansion on a beach. (incorrect verb tense)

Here are some additional examples:

• If she were my sister, I would have a built-in best friend.
• If I found an unexpected inheritance, I would build a new house from the ground up.

Third Conditional Sentences

The third conditional sentence is for things that did not happen in the past due to the if clause. This sentence structure often indicates a sense of regret.

These sentences follow this pattern:

• If + past perfect, modal + present perfect.

Here is the third conditional in a sentence:

• If I had known there was a traffic jam, I would have left 10 minutes early.

A common mistake with this type of conditional is using the modal auxiliary in the conditional clause, as in:

• If I would have known there was a traffic jam, I would have left 10 minutes early.

Here are some additional examples:

• If it had rained earlier this week, the plants wouldn’t have wilted.
• If I had finished my degree, I would have become a dentist.

Mixed Conditional Sentences

Mixed conditional sentences are not considered one of the four types because these mix the second and third conditionals into one statement. It can follow one of two patterns:

• If + past perfect, modal + base.
• If + simple past, would/could present perfect.

These sentences present an unreal condition that occurred in the past or will occur in the future and connect that condition with an imaginary potential result. Here are some examples:

• If I had finished my degree, I would be a teacher now.
• If it had rained earlier this week, the plants would be alive.
• If you were kinder, you would have made more friends.
• If you worked harder, you would have gotten a promotion last year.

Categorizing Conditional Sentences

In addition to the four main types of conditionals, these sentences can be labeled “real” or “unreal” based on whether or not their meaning is possible. In zero and first conditionals, the meaning is always possible, so these are real.

However, second, third, and mixed conditionals typically are hypothetical situations or are about past events that the writer can’t change. This makes them impossible, which means they are “unreal.” The typical reason to make an unreal conditional sentence is not to state what will happen but rather to make a point.

Exceptions to the Conditional Sentences Rules

In English grammar, exceptions are common, and conditional sentences fall into this category.

First, you can use the simple future tense in the if-clause in one instance. If the action in the if-clause will take place after the action that occurs in the main clause, the simple future tense is appropriate. Here is an example:

• If it will calm you down, I will tell you how to stay safe in a thunderstorm.
• If it will help with the discomfort, I will wear my leg brace when I go hiking.

Because the actions of calming the listener down or easing the discomfort only happen if the actions of telling about safety or wearing the leg brace occur, then future perfect tense applies.

Second, if the conditional sentence uses “were to” in the if-clause, it indicates that the main conditional clause is a particularly bad scenario. This changes the verb tense and also adds emphasis to the sentence. Here are some examples:

• If she were to call in sick, she would get laid off.
• If the dog were to bite the neighbor, he would have to be taken to the shelter.

Conditional Sentences and Punctuation

When you write a conditional sentence, you may find punctuation to be a challenge. However, the rule is very simple. All you need to do is add a comma after the if clause if the if clause comes before the main clause. Since this is the usual structure, you add the comma between the two clauses to punctuate it well.

The Need for Conditional Sentences in Essay Writing

Understanding conditional sentences and how to use the right verb tenses to convey these meanings is vital to essay writing in school. First, using conditional sentences correctly gives your essay correct grammar. Correctness and precision are vital in academic writing.

Also, when you use the appropriate sentence structure, you create essays with greater clarity. Your reader will understand the meaning of the sentence and whether or not the conditional you set up could or will happen.

Conditional sentences also help with grading essays in school. Teachers will be able to understand your meaning clearly, and this understanding helps them grade the essay appropriately.  

Common Problems with Conditional Sentences

All English speakers will make some common mistakes with conditional sentences, and you should know how to watch for these in your writing and speaking.

1. Using a Comma Incorrectly

If the if-clause proceeds the main clause, it gets a comma. However, if it comes after the main clause, it does not. Here is an example:

• You will be late if you don’t leave soon.

In this sentence, you would not place a comma between “late” and “if.” However, if you reversed the order, you would:

• If you don’t leave soon, you will be late.

Only use the comma if the if clause comes first.

2. Using the Wrong Tense

Another common mistake is mixing up the tenses and thus showing the wrong meaning in the sentence. Depending on the meaning you wish to convey, you need to use the right verb tense. Here are some examples and their corrections:

• If you sleep, you will dream.

This sounds right, but it is a zero conditional sentence. Thus, it should have the simple present tense in the main clause. Here is the corrected version:

• If you sleep, you dream.

Here is a first conditional sentence example:

• If you will help other people, you will have everything you need in life.

In this example, the if clause should have the simple present tense, reading as follows:

• If you help other people, you will have everything you need in life.

This sentence is a poor example of the second conditional sentence:

• If you become a mother, you would understand unconditional love.

The second conditional should have simple past tense in the if clause, like this:

• If you became a mother, you would understand unconditional love.

Finally, for the third conditional sentence, some writers will insert “would have” into the if clause, like this:

• If you would have gone to bed early, you would have gotten enough sleep.

Instead, this should use the past perfect tense in the if-clause, like this:

• If you had gone to bed early, you would have gotten enough sleep.

When writing conditional sentences, you can’t always rely on your speaking abilities. Take time to learn the proper verb tenses, so you can use them correctly when writing these sentences.

How to Use Conditional Sentences in Your Next Essay

Using conditional sentences correctly will make your next essay clearer and stronger. To do so, first, decide the meaning of your if/then statement. Do you intend to convey something certain, something that is unlikely to happen, or something impossible?

Once you know the meaning, you can choose the correct format. Choose the right verb tense and structure based on the information here, and write the sentence correctly.

When proofreading your academic paper or essay, look for if-clauses. If you have them, make sure the structure fits the intended meaning based on the four types of conditional sentences. This practice will give you clear, correct writing for your papers. Finally, check the list of common errors to make sure you are not making any of these in your writing. These errors often sound correct, but they do not convey the right meaning. Eliminate them to make your writing grammatically correct and clear to your readers.

If you still need help, our guide to grammar and syntax explains more.