Conditional Sentences

NOTE: For More Practice of Conditional Sentences, try exercise containing sentences with “if”

Click for sentences with “if”

Explanation 1

Parts of Conditional Sentences

A conditional sentence has two clauses that really rely on each other to make sense—a conditional clause (which is a dependent clause) and a main clause (which is the independent clause). The tenses of these clauses determine the type of conditional sentence, which the next section will explain.

a. Conditional Clause

The conditional clause is a dependent clause beginning with “if.” All conditional sentences have a clause beginning with “if” because it expresses the conditions (what must or might have happen), like this:

• If you want
• If I am late to school
• If you don’t do your homework
• If I hadn’t eaten so much candy

Whenever a clause begins with “if,” it depends on more information to be complete—it must be paired with an independent clause. So, the dependent clause is only half of a conditional sentence, and couldn’t be a sentence on its own.

b. Main Clause

The main clause is what provides the rest of the information to complete a conditional sentence. It’s an independent clause that states the result of the conditional “if” clause. In other words, it’s the “then” part of an if/then situation. In these examples, the main clauses are orange.

• If you want, I can go with you to the store.
• If I am late to school, I will get detention.
• If I don’t do my homework, the teacher yells.
• If I hadn’t eaten so much candy, I might be hungry.

As you can see, these main clauses express complete thoughts and can be sentences on their own. But, you can also see that we also need them to complete the thoughts of the dependent clauses!

Four types of Conditional Sentences

As a rule, conditional sentences are categorized by whether their situations are “real” or “imagined.” However, there are many types and forms of conditional statements, and they can be quite complicated, varying depending on time, its likeliness of occurring, and other factors. This article will help you understand the basics, and teach you how to recognize a conditional sentence when you see one.

a. “Real” Conditionals (Zero Conditional)

Real conditionals (also called zero conditionals) are sentences expressing the real conditions for things that happen, not hypothetical things (see Imagined Conditionals). They share true statements about things that will happen or do happen in certain conditions or circumstances.

Zero conditional sentences can come in many forms. But since they are based in fact, they only share past and present situations, NOT possible future situations. So, we write them using a combination of past and present tenses.

Present Tense

In many zero conditional sentences, both clauses are in the present simple tense, like this:

• If you are happy, I am happy.
• If there is snow, we make snowmen.
• He cleans if I cook.
• f you don’t mind, I need a glass of water.

But we also write them using other present tenses, like this:

Present continuous + Present simple

• If it is snowing, we don’t drive.
• I eat at home if Jane is cooking dinner.

Present continuous + Present continuous

• If he is staying, I am going.
• If the plant is dying, you are not watering it.

All of these examples express that every time A happens, B happens or we do B.

Past Tense

Zero conditionals can also reflect situation that already happened, like this:

Past simple + Past simple

• If it snowed, we never drove.
• If we had chocolate chips, we made cookies.

Past simple + Past continuous

• We always made snowmen if it was snowing.
• If Jane was cooking, I ate at home.

b. “Imagined” Conditionals

We use imagined conditional sentences to talk about hypothetical or “imagined” conditions that are possible, likely, or even impossible. Based on the level of possibility, there are three conditionals: first, second, and third.

First Conditional

The first conditional shares the result of situation in the future that we think is pretty likely to happen. Its form uses a conditional clause in the present simple, and the main clause in the future tense. The main clause will use a modal, like would, should, could, will, may, might, or can. Here are some examples:

• If I sleep now, I will be up all night.
• If I do well on my SATs, I could go to Harvard.
• If you take the highway, you might hit traffic.
• If he likes cookies, you should bake some for him.

Of all the conditionals, the first conditional expresses things that are most possible or likely to happen. As we will explain, with the second and third conditionals, things become less likely or even completely imagined.

Second Conditional

The second conditional shows possible outcomes that could occur in the present or future, if specific conditions exist. To put it simply, second conditionals reflect ideas of “if you did this, this can happen.” BUT, the “did” hasn’t actually happened yet, it’s just possible.

The second conditional’s form uses a conditional clause in the past simple, and the main clause in the future tense, also using modals. Here are some examples:

• If you slept until 3pm, you shouldn’t be tired.
• If you did well on the SATs, you will get accepted.
• If you wanted to avoid traffic, you could take the highway.
• If he ate all the cookies, you would have to bake more.

On a special note, the English language lets us use the past tense to reflect hypothetical situations that aren’t based in reality. So, even though the second conditional uses the past tense in the conditional clause, it’s expressing what could happen “if,” not what did already happen. It still expresses the present and future because the ideas are only possibilities. It also helps us use more polite language like this:

• If you wanted, I could help you study.
• If you needed me to, I could pick up your dry cleaning.
• If you wouldn’t mind, I could use some help.

Third Conditional

The third conditional lets us contemplate what could have happened if things went differently in the past. It lets us reflect upon things in the way of “if this had happened, this could have happened.”

Its form uses the past perfect for the conditional statement, and the conditional perfect tense (would have + verb) for the main clause (you can also use other modals instead of would). Here are some examples:

• If you had gone to bed earlier, you would have been well rested.
• If you had done well on the SATs, you would have been accepted.
• If you had taken the highway, you could have avoided traffic.
• If you had made more cookies, we might have had enough.

As you can see, these sentences only reflect what possibly could have happened—not what still can or might happen.

c. Other Forms

There are several other special forms of conditions, like mixed conditionals and conditional sentences using will or would.

Mixed Conditionals

Sometimes we can mix the tenses to express conditions. Mixed conditionals reflect things that did or did not happen in the past that are still relevant now and in the future. We form a mixed conditional with the past perfect tense in the conditional statement and using would in the main clause of the sentence. Here are some examples:

• If I hadn’t slept, I would be very tired.
• If I had made more cookies, he would be eating them.
• If there had not been traffic, I would be on time.
• If I had failed the SATs, I would not be at Harvard.

Conditionals Using Will or Would

In English, will and would can refer to either the present or the future. That’s because we use will and would to express willingness to do something. Here are some examples:

• If you will cook, I will clean.
• If he would pick up the cookies, that would be great.
• If you would show me the way, I will be very grateful.
• If you would just stop crying, I will try to help you.

5. How to Write a Conditional Sentence

In a way, conditional sentences are some of the easiest to write because they always include certain things—particularly a conditional clause beginning with “if.” We can use them for both real and imagined scenarios, and to express all kinds of possibilities and hypothetical situations. What’s more, conditional sentences let us do these things by mixing together the past, present and future tenses without many restrictions.

When you want to use conditional sentences, you can just stick by these guidelines:

1. You always need 2 clauses:

• a conditional clause beginning with “if”
• a main clause

2. Present pieces of information that rely on each other:

• the goal is to show that if one thing happens, another thing will happen.

3. Choose your tenses based on 2 things:

• whether the situation is “real” or “imagined”
• if it reflects past, present or future possibilities

Finally, here’s a chart to help you see the differences between the conditionals. It’s a lot to remember!

Zero (True)	First (Likely)	Second (Less Likely)	Third (Impossible)	Mixed (Possible)	Would/Will (Probable)
If he makes cupcakes, we eat them.	If he makes cupcakes, we will eat them.	If he made cupcakes, we would eat them.	If he had made cupcakes, we would have eaten them	If he had made cupcakes, we could be eating them.	If he would make cookies, I will eat them.

Explanation 2

Conditional Sentences

There are four types of conditional sentences.

It’s important to use the correct structure or each of these different conditional sentences because they express varying meanings.Pay attention to verb tense when using different conditional modes.

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:

1. If a certain condition is true, then a particular result happens.
2. I would travel around the world if I won the lottery.
3. When water reaches 100 degrees, it boils.
4. If you love me, let me go!
5. I wouldn’t be here if I had never met you.
6. If opportunity knocks, open the door.
7. You can’t be shy if you want to make friends.
8. If he comes, ask him to wait.
9. If it rains, we will get wet.
10. If you study hard, you will pass your exam.
11. If I had time, I would go  shopping with you.
12. If you speak  English, you will get along with them perfectly.
13. If they had gone for a walk, they would have turned  the lights off.
14. If she comes  to see us, we will go to the zoo.
15. I would have told you, if I had seen  him.
16. Would you mind if I opened  the window?
17. If they had invited  me, I wouldn’t have said no.
18. My friend will meet  me at the station if he gets the afternoon off.
19. If I didn’t do  it, nobody would do it.
20. If my father doesn’t pick  me up, I’ll take the bus home.
21. If it had rained, you would have gotten wet.
22. You would have gotten wet if it had rained.
23. You would have passed your exam if you had worked harder.
24. If you had worked harder, you would have passed your exam.
25. I would have believed you if you hadn’t lied to me before.
26. If you hadn’t lied to me before, I would have believed you.

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.

1. Zero Conditional Sentences
2. First Conditional Sentences
3. Second Conditional Sentences
4. 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 cause 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:

1. If you don’t brush your teeth, you get cavities.
2. 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 . (Incorrect)

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.

How to Use First Conditional Sentences

First conditional sentences are used to express situations in which the outcome is likely (but not guaranteed) to happen in the future. Look at the examples below:

If you rest, you will feel better. (Incorrect)

• If you set your mind to a goal, you’ll eventually achieve it.

Note that we use the simple present tense in the if-clause and simple future tense in the main clause—that is, the clause that expresses the likely outcome. This is how we indicate that under a certain condition (as expressed in the if-clause), a specific result will likely happen in the future. Examine some of the common mistakes people make using the first conditional structure:

1. If you will rest , you will feel better.
2. If you rest , you will feel better.

Explanation: Use the simple present tense in the if-clause.

If you set your mind to a goal, you eventually achieve it. (Incorrect)

If you set your mind to a goal, you’ll eventually achieve it.

Explanation: Use the zero conditional (i.e., simple present + simple present) only when a certain result is guaranteed. If the result is likely, use the first conditional (i.e., simple present + simple future).

How to Use Second Conditional Sentences

Second conditional sentences are useful for expressing outcomes that are completely unrealistic or will not likely happen in the future. Consider the examples below:

1. If I inherited a billion dollars, I would travel to the moon.
2. If I owned a zoo, I might let people interact with the animals more.

Notice the correct way to structure second conditional sentences is to use the simple past tense in the if-clause and an auxiliary modal verb (e.g., could, should, would, might) in the main clause (the one that expresses the unrealistic or unlikely outcome). The following sentences illustrate a couple of the common mistakes people make when using the second conditional:

If I inherit a billion dollars, I would travel to the moon. (Incorrect)

• If I inherited a billion dollars, I would travel to the moon.

Explanation: When applying the second conditional, use the simple past tense in the if-clause.

If I owned a zoo, I will let people interact with the animals more. (Incorrect)

If I owned a zoo, I might let people interact with the animals more.

Explanation: Use a modal auxiliary verb in the main clause when using the second conditional mood to express the unlikelihood that the result will actually happen.

How to Use Third Conditional Sentences

Third conditional sentences are used to explain that present circumstances would be different if something different had happened in the past. Look at the following examples:

1. If you had told me you needed a ride, I would have left earlier.
2. If I had cleaned the house, I could have gone to the movies.

These sentences express a condition that was likely enough, but did not actually happen in the past. The speaker in the first sentence was capable of leaving early, but did not. Along these same lines, the speaker in the second sentence was capable of cleaning the house, but did not. These are all conditions that were likely, but regrettably did not happen.

Note that when using the third conditional, we use the past perfect (i.e., had + past participle) in the if-clause. The modal auxiliary (would, could, shoud, etc.) + have + past participle in the main clause expresses the theoretical situation that could have happened.

Consider these common mistakes when applying the third conditional:

If you would have told me you needed a ride, I would have left earlier. (Incorrect)

• If you had told me you needed a ride, I would have left earlier.

Explanation: With third conditional sentences, do not use a modal auxiliary verb in the if-clause.

If I had cleaned the house, I could go to the movies. (Incorrect)

• If I had cleaned the house, I could have gone to the movies.

Explanation: The third conditional mood expresses a situation that could have only happened in the past if a certain condition had been met. That’s why we use the modal auxiliary verb + have + the past participle.

FORM

In a Type 3 conditional sentence, the tense in the ‘if’ clause is the past perfect, and the tense in the main clause is the perfect conditional or the perfect continuous conditional.

If clause (condition)	Main clause (result)
If + past perfect	perfect conditional or perfect continuous conditional
If this thing had happened	that thing would have happened.

As in all conditional sentences, the order of the clauses is not fixed. You may have to rearrange the pronouns and adjust punctuation when you change the order of the clauses, but the meaning is identical.

EXAMPLES

• If it had rained, you would have gotten wet.
• You would have gotten wet if it had rained.
• You would have passed your exam if you had worked harder.
• If you had worked harder, you would have passed your exam.
• I would have believed you if you hadn’t lied to me before.
• If you hadn’t lied to me before, I would have believed you.

FUNCTION

The type 3 conditional refers to an impossible condition in the past and its probable result in the past. These sentences are truly hypothetical and unreal, because it is now too late for the condition or its result to exist. There is always some implication of regret with type 3 conditional sentences. The reality is the opposite of, or contrary to, what the sentence expresses. In type 3 conditional sentences, the time is the past and the situation is hypothetical.

EXAMPLES

• If I had worked harder I would have passed the exam. (But I didn’t work hard, and I didn’t pass the exam.)
• If I had known you were coming I would have baked a cake. (But I didn’t know and I didn’t bake a cake.)
• I would have been happy if you had called me on my birthday. (But you didn’t call me and I am not happy.)

In type 3 conditional sentences, you can also use modals in the main clause instead of “would” to express the degree of certainty, permission, or a recommendation about the outcome.

EXAMPLES

• If I had worked harder I might have passed the exam.
• You could have been on time if you had caught the bus.
• If he called you, you could go.
• If you bought my school supplies for me, I might be able to go to the park.

CONTRACTIONS

Both would and had can be contracted to ‘d, which can be confusing if you are not confident with type 3 conditional sentences. Remember 2 rules:
1. would never appears in the if-clause so if ‘d appears in the if clause, it must be abbreviating had.
2. had never appears before have so if ‘d appears on a pronoun just before have, it must be abbreviating would.

EXAMPLES

• If I’d known you were in hospital, I’d have visited you.
• If I had known you were in hospital, I would have visited you.
• I’d have bought you a present if I’d known it was your birthday.
• I would have bought you a present if I had known it was your birthday.
• If you’d given me your e-mail, I’d have written to you.
• If you had given me your e-mail, I would have written to you.

THE PERFECT CONDITIONAL TENSE

The perfect conditional of any verb is composed of three elements:
would + have + past participle
Have followed by the past participle is used in other constructions as well. it is called the “perfect infinitive”.

Subject	+ would	+ have	+ past participle
He	would	have	gone
They	would	have	stayed

TO GO: PERFECT CONDITIONAL

Affirmative	Negative	Interrogative	Interrogative Negative
I would have gone	I wouldn’t have gone	Would I have gone?	Wouldn’t I have gone?
You would have gone	You wouldn’t have gone	Would you have gone?	Wouldn’t you have gone?
He would have gone	He wouldn’t have gone	Would he have gone?	Wouldn’t he have gone?
She would have gone	She wouldn’t have gone	Would she have gone?	Wouldn’t she have gone?
We would have gone	We wouldn’t have gone	Would we have gone?	Wouldn’t we have gone?
They would have gone	They wouldn’t have gone	Would they have gone?	Wouldn’t they have gone?

Exceptions and Special Cases When Using Conditional Sentences

As with most topics in the English language, conditional sentences often present special cases in which unique rules must be applied.

Use of the Simple Future in the If-Clause

Generally speaking, the simple future should be used only in the main clause. One exception is when the action in the if-clause will take place after the action in the main clause. For example, consider the following sentence:

If aspirin will ease my headache, I will take a couple tonight.

The action in the if-clause is the aspirin easing the headache, which will take place only after the speaker takes them later that night.

“Were to” in the If-Clause

The verb phrase were to is sometimes used in conditional sentences when the likely or unlikely result is particularly awful or unthinkable. In this case, were to is used to place emphasis on this potential outcome. Consider these sentences:

1. If I were to be sick, I would miss another day of work.
2. If she were to be late again, she would have to have a conference with the manager.
3. If the rent were to have been a penny more, they would not have been able to pay it.

Note that the emphatic “were to” can be used to describe hypothetical scenarios in the present, future, and past.

Punctuating Conditional Sentences

Despite the complex nature of conditional sentences, punctuating them properly is really simple!

• Here’s the skinny:

Use a comma after the if-clause when the if-clause precedes the main clause.

1. If I’d had time, I would have cleaned the house.
2. If the main clause precedes the if-clause, no punctuation is necessary.
3. I would have cleaned the house if I’d had time.