Put a comma after the if-clause when it comes before the main clause. Put commas around the if-clause when it is in the middle of the main clause.
English Articles
Conditional sentences in English: What are they and how to use them?
By: Anna Classing Wed Oct 02 2024
A conditional is a type of sentence that says that one situation depends on another. Because there are always two situations described, a conditional sentence always has two parts: a condition and a result. They are also known as “if-sentences,” because the part that describes the condition usually starts with “if,” for example:
conditionresult
If I get up early, I practice yoga in the morning.
If I get up early tomorrow, I will practice yoga.
If I got up early every day, I would practice yoga in the mornings.
If I had gotten up early yesterday, I would have practiced yoga.
To use conditional sentences in English, you will need to learn some special grammar because their structure shows the time frame for the condition and its consequences, as well as the probability that they will actually happen. Conditionals are commonly divided into four types (first, second, third, and zero conditionals), each with its own structure, so let’s unpack each of them in turn.
Table of Contents
What are parts of a conditional sentence?
Conditional sentences usually consist of a conditional clauseNo definition set for clauseLorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. (an "if" clause) and a main clause (a "then" clause).
A conditional clause sets a condition, which can be plausible (possible or likely to happen) or implausible (impossible, imaginary, or very unlikely to happen). A conditional clause is a type of dependent clauseNo definition set for dependent clauseLorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum., because it doesn’t really make full sense without a main clause.
A main clause describes what happens as a result of the situation in the conditional clause. The condition may never be met, but if it is met, the main clause is the result
The conditional clause may come before, after, or (rarely) in the middle of the main clause.
conditional clausemain clause
If you want, you can come early and help.
You can come early and help if you want.
You can, if you want, come early and help.
Tip
When the main clause follows the if-clause, it can begin with then, which is why the main clause is sometimes called the “then-clause” and why conditional sentences are sometimes called if-then sentences.
conditional clausemain clause
If you go to bed early, then you will feel better in the morning.
The main clause may also be a question:
conditional clausemain clause
If you get a dog, will you walk it early in the morning every day?
If is the most common word we use to introduce conditional clauses, but there are others, too. They are called “conjunctions of condition” and differ slightly in meaning and degree of formality
provided / providing (that)
so/as long as
on condition that
suppose / supposing
unless
in case
You can read more about how to use these conjunctions of condition in our post on English conditionals without if!
Important
Do not use then in the main clause if the conditional clause starts with any other words but if.
What are the types of conditionals in English?
There are four main types of conditionals in English (zero, first, second, third) and a “mixed” type which has features of each. Each type of conditional is used in a different circumstance, depending on how plausible(possible, likely, real) or implausible(unlikely, impossible, imaginary) the condition is, and each has its own grammar.
Conditional type | General meaning | Example |
|---|---|---|
Zero | Used to give the results that always come from a possible situation | If I don’t sleep enough, I feel sick. → This always happens. |
1st | Used to give the results of a possible situation in a specific case. | If we take a vacation this summer, we’ll go to the beach. → This will happen in one situation. |
2nd | Used to give the results of an imaginary or very unlikely situation. | If Jennifer were a millionaire, she would buy a new house. → Jennifer is not and probably will not be a millionaire. |
3rd | Used to give the imaginary result of an imaginary past situation → a condition that was not met. | I would have played basketball in school if I had been taller. → But I was not actually tall when I was in school. |
Mixed | Any combination of the types given above | I wouldn’t own a business now if I hadn’t taken a loan back in 1998. → This example uses the 2nd and 3rd conditional, respectively. |
Here is a summary of the grammar rules that usually go with each type of conditional:
Conditional type | Conditional clause (if) | Main clause (then) |
|---|---|---|
Zero | present simple | present simple |
1st | present simple | future with will |
2nd | past simple | will + verbNo definition set for verbLorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. |
3rd | past perfect | would + have + past participleNo definition set for past participleLorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum. |
Mixed | any of the above | any of the above |
Let’s look at each type in more detail!
Zero conditionals
Use a zero conditional to describe the result that always happens when the condition is true. The most typical structure for zero conditionals is:
If
present simple
present simple
If a honeybee stings, it dies.
I always travel abroad if my vacation is longer than a week.
Zero conditional sentences describe universal truths, such as scientific facts or typical/repeated personal situations. That is why we use the English present simple — because this is the tense we usually use for general truths.
In zero conditionals, if is very close in meaning to when or whenever:
Dad snores if he sleeps on his back.
= Dad snores when he sleeps on his back.
= Dad snores whenever he sleeps on his back.
Here are some more examples of zero conditionals in English:
If a car moves at 55 mph, its braking distance is about 180 feet.
If it snows a lot in this area, the roads are closed.
What do we have to do if smoke detectors go off?
If I don’t feel like cooking, I can always order pizza.
If he sees a celebrity, he must ask for a selfie.
Tip
In a zero conditional, you can always add the word always to the main clause! Try it with the sentences above .
Exception!
While not as common, you can use other verb tenses to make a zero conditional sentence as long as the tense is exactly the same in both the if-clause and the then-clause, and you are still talking about general truths and recurring situations, for example:
- present continuous
If I am listening to a good song I'm singing too!
- past simple
I always traveled abroad if my vacation was longer than a week.
First conditionals
Use a first conditional to describe a result that will happen in one specific case when the condition is true. The condition here is always possible. A typical first conditional sentence looks like this:
If
present simple
future with will
If you oversleep tomorrow, you will be in a lot of trouble.
He’ll break the world record if if he scores another goal.
First conditional sentences are used to talk about future events that depend on a “real” condition, that is, a condition which is still possible, but we just don’t know for certain that it will happen.
Important
The most important thing to remember about the structure of the first conditional sentences is that we use the present tense in the if-clause even though it has a future meaning. For example:
If she buys a motorcycle, she won’t be able to drive it much in winter here.
→ Will she buy a motorcycle in the future?We will go to the party if we find a babysitter.
→ Will we find a babysitter in the future?
We do not use will in the if-clause!
❌ If I will get this job, what will my typical day at work be like?
✅ If I get this job, what will my typical day at work be like?
First conditionals are used for negotiating, discussing plans and back-up plans, giving advice and threats, making promises, and giving warnings.
Exception!
In first conditional sentences, you can use other tenses after if (as long as there is no will) and you can form the future in the main clause without will (as long as it still has future reference). For example:
conditional clause (without "will")main clause (future reference)
If you’re coming tomorrow evening, we can stop for dinner on the way home.
I can help you with dinner if you’ve finished cleaning.
The car might get stuck if it’s been snowing longer than three hours.
If you are going to make salad, I’ll bring a dessert.
Second conditionals
Use a second conditional sentence to describe the imaginary result of an imaginary situation in the present or future. The most typical structure for the second conditional is
If
past simple
would + root
If you had a superpower, what would it be?
He wouldn’t have a dog if he didn’t have a big backyard.
The most striking feature of the second conditional is that the tenses are all “back-shifted.” This means that, even though we are discussing an imaginary situation in the present or future:
We use the past simple in the if-clause.
We use would rather than will in the main clause.
Second conditional sentences describe imaginary situations in the present and in the future. The imaginary situation is sometimes technically possible, but you’re not really making a plan, it’s just a hypothetical discussion. The condition can, therefore, be called “unreal,” as the speaker thinks that the situation is unlikely or impossible, for example:
If I bought a smaller house, I would spend less time cleaning!
→ It is technically possible for me to buy a small house in the future, but I do not really plan to move, so the situation is imaginary or speculative.
I wouldn’t ask you for cash if I were rich.
→ I am not rich. Someday, I might become rich, but that does not impact the situation now, so I am only imagining being rich. I am not making a plan.
Important
Did you see the form of the verb be in that second example? When you use the verb be in the conditional clause of a second conditional, the correct form of the verb is always were, not was! We use were with both singular and plural subjects.
✅ If she were taller, she could ride the roller coaster.
Although were is considered the standard or correct form, native speakers very often use was, where you would use it in a normal past tense sentence, especially in speech.
If I were/was the owner of this company, I would change its logo.
If she were/was English, she would not need an interpreter.
Lucy wouldn’t be working here if she weren’t/wasn’t enjoying it.
Here are two common variations on the second conditional:
It is possible to use past continuous after if too, as long as would is also followed by be + present participle (verb + -ing), for example:
past continuousIf I weren’t driving now, I would be watching the game.
You can replace would in the main clause with other English modal verbs, especially could or might,
I might stay longer if I didn’t have a return ticket.
I could be a basketball star if I was a little taller.
When to use the second conditional?
The second conditional is used to talk about imaginary situations, wishes, fantasies, and to discuss various hypothetical scenarios. These are all implausible conditions, but how implausible they are can vary. For example, the condition can be…
tentative but possible
If we bought tickets in advance, we could probably get a discount.
→ We still can buy tickets in advance, but I’m still imagining a variety of plans.imaginary but not impossible
If I found a job in Tokyo, I would move there without hesitation.
→ It is unlikely that I will find one, but I can imagine it.totally unreal and contrary to the actual fact
If I had an older brother, he would teach me how to play football.
→ I do not have an older brother, so this is purely hypothetical.
Important
Because the future can never really be certain, the difference between “real” conditionals and “unreal” conditionals is sometimes not important, and it is often up to a speaker to choose how to put it best. For example, these two sentences have mostly interchangeable meanings:
I’ll be shocked if it turns out to be true. → “real” conditional (1st)
I’d be shocked if it turned out to be true. → “unreal” conditional (2nd)
Sometimes, however, there is actually a difference in meaning between first and second conditionals that makes one sound more possible than the other. For example:
If I win the lottery, I’ll buy a new car. → “real” conditional (1st)
→ You probably already have a ticket.If I won the lottery, I’d buy a new car. → “unreal” conditional (2nd)
→ You probably don’t have a ticket.
Third conditionals
Third conditional sentences are used to talk about missed opportunities in the past. The condition is always something that did not happen or is contrary to the past fact, and so the main clause describes a past that also didn’t happen. Third conditionals are used to talk about re-imagined history and biography, coincidences, regrets, or lucky escapes.
The basic structure for third conditional sentences is:
If
past perfect
would + have + past participle
He would have cooked more food if he had known you were coming.
→ He did not know you were coming, so he did not cook more food.
If I hadn’t gone to Europe that summer I wouldn’t have met my wife.
→ I did go to Europe that summer so I did meet my wife.
The tenses in the third conditional are “back-shifted” like the tenses in the second conditional, but because here we are talking about a past situation they are shifted to a further past by using the past perfect and would have + past participle:
If he had eaten more, he would have had more energy.
→ He did not eat much, so he did not have energy.I would have gotten there on time if there hadn’t been an accident on the bridge.
→ There was an accident on the bridge, and I didn’t get there on time.
Some common variations on the third continuous:
The past perfect continuous is also possible in the if-clause:
I wouldn’t have won the contest if I hadn’t been practicing for days.
Other modal verbs, such as could or might, can be used instead of would, and the past perfect continuous:
If I had been there before, I might have known where to go.
TipSound like a native!
In speech, you can use contracted forms of would, have, had, and not:
We’d’ve bought that house if it hadn’t been on a hill.
He wouldn’t’ve left if he’d known you were coming.
Sometimes contractions can go really wild in everyday speech in English! For example:
Y’all’d’ve died from envy if you’d seen me on the stage!
You all would have
Mixed conditionals
The four types of conditional sentences described above are not isolated from each other. Instead, it’s possible to combine an if-clause of one type with a main clause of another type. For example:
- second conditional (past reference)zero conditional (present reference)
If I misunderstood you and let everyone down that day, then I am truly sorry.
→ Condition: a past situation that is unlikely/imagined
→ Result: something that is always true now when the condition is met - third conditional (past reference)second conditional (present reference)
If she hadn’t brought extra socks, Johnny’s feet would be wet and dirty now.
→ Condition: a past situation that did not happen (she did bring socks)
→ Result: a situation in the present that is imagined - third conditional (past reference)second conditional (present reference)
You would have been fired if your manager weren’t so understanding.
→ Condition: a present situation that is imagined (your manager is understanding)
→ Result: a past situation that did not happen (you were not fired) - second conditional (future reference)first conditional (future reference)
If you would postpone the party until Sunday, I’ll definitely be there.
→ Condition: an imagined situation in the future
→ Result: a planned future situation
The most popular types to mix together are the second and the third conditionals, but virtually any combination of the four types is possible.
Conclusion
Conditional sentences consist of an if-clause and a main clause, and belong to one of the following types:
Zero conditionals (present simple + present simple) talk about general truths.
First conditionals (present simple + will) talk about “real” conditions and their consequences in future.
Second conditionals (past simple + would + verb) talk about “unreal” conditions and their consequences in present and future.
Third conditionals (past perfect + would have + past participle) talk about “unreal” conditions and their consequences in the past.
Mixed conditionals (an if-clause of one type, a main clause of another type)
Try practicing conditional sentences in English with these English conditional sentences activities! Or, if you’d rather learn about some other ways to create conditional sentences without using the word if, have a look at our post on English conditionals without if!
