By Vahid Alaghehband
Conditionals combine a condition (if…) and a result. The zero conditional is for general facts (If you heat ice, it melts); the first, for possible future situations (If it rains, I'll stay home); the second, for imaginary present situations (If I had more time, I would travel); and the third, for a past that didn't happen (If I had studied, I would have passed).
This guide is part of English grammar by level. Conditionals are A2 and B1 grammar on the CEFR (A2.2–B1.2 in the Vozi Grammar catalog). Zero and first conditionals are A2 grammar; second and third conditionals are B1.
How to form conditionals
| Type | Condition (if) | Result | Example |
|---|---|---|---|
| Zero | if + present simple | present simple | If you mix blue and yellow, you get green. |
| First | if + present simple | will + verb | If you call me, I'll pick you up. |
| Second | if + past simple | would + verb | If I lived near the beach, I would swim every day. |
| Third | if + had + past participle | would have + past participle | If we had left earlier, we wouldn't have missed the bus. |
Affirmative, negative and question (first conditional)
| Form | Example |
|---|---|
| Affirmative | If it's sunny, we'll go to the park. |
| Negative | If you don't hurry, you won't catch the bus. |
| Question | What will you do if they offer you the job? |
| Short answer | Will you come if I invite you? — Yes, I will. |
The two parts can go in either order; if if comes first, use a comma: If it rains, I'll stay home / I'll stay home if it rains. In the second conditional, If I were you is used to give advice.
When to use conditionals
Zero: facts, rules and instructions
The result always happens when the condition is true.
- If you press this button, the screen turns off.
- If I drink coffee at night, I can't sleep.
- Plants die if they don't get water.
First: real possibilities in the future
The condition can happen.
- If you study every day, you'll improve fast.
- If she doesn't answer, I'll send a message.
- What will you do if the flight is canceled?
Second: imaginary situations and advice
Something that isn't real now or that you think is unlikely.
- If I won the lottery, I would buy a house for my mom.
- If I were you, I'd ask for a raise.
- Would you move abroad if you had the chance?
Third: a past that didn't happen
You imagine a different result for something that already happened; useful for regrets.
- If I had known, I would have helped you.
- She would have passed if she had practiced more speaking.
- If we hadn't taken that road, we wouldn't have met.
Key words
Besides if, these words introduce conditions:
- if
- unless (= if not)
- when (zero)
- as long as
- provided (that)
Note: in case is not the same as if. Take an umbrella in case it rains means as a precaution, because it might rain; it doesn't mean you only take it if it rains.
Common mistakes
| Mistake | Correction | Why |
|---|---|---|
| ✗ If it will rain, I'll stay home. | ✔ If it rains, I'll stay home. | Don't use will after if. The same goes for when: when it rains, not when it will rain. |
| ✗ If I would have money, I would buy it. | ✔ If I had money, I would buy it. | In the second conditional, would goes only in the result. |
| ✗ If I had studied, I would passed. | ✔ If I had studied, I would have passed. | The third conditional needs would have + past participle. |
| ✗ If I was you, I'd call her. | ✔ If I were you, I'd call her. | For advice, were is preferred, especially in exams and formal writing; was is also heard in conversation. |
| ✗ Unless you don't hurry, you'll be late. | ✔ Unless you hurry, you'll be late. | Unless already means "if not": don't add another negative. |
First vs second conditional
| First conditional | Second conditional | |
|---|---|---|
| How likely | Real, possible | Imaginary or unlikely |
| Tenses | if + present, will + verb | if + past, would + verb |
| Example | If I get the job, I'll move to Cuenca. (my interview is tomorrow) | If I got the job, I'd move to Cuenca. (I don't think I'll get it) |
| Real time | Future | Imagined present or future |
The past tense in the second conditional doesn't refer to the past: it shows distance from reality.
Short conversation
Two friends talk about a level exam.
A: What will you do if you pass the B2 exam?
B: If I pass, I'll apply for a scholarship in Canada.
A: And if you don't pass?
B: If I don't pass, I'll take it again in March.
A: I'm sure you'll do fine. If I were you, I'd practice speaking every day.
B: You're right. Last year I didn't. If I had practiced more, I would have gotten a better score.
A: Well, this time you know what to do.
B: Exactly. If I have questions, I'll call you!
10 exercises with answers
Complete with the correct form of the verb. In the last one, fix the mistake.
- If you heat water to 100 °C, it ___ (boil).
- If it ___ (rain) tomorrow, we'll cancel the trip.
- If I ___ (have) a car, I would drive to work.
- She ___ (call) you tomorrow if she needs help.
- If they ___ (leave) earlier, they would have caught the train.
- If I were you, I ___ (not / buy) that phone.
- What ___ you ___ (do) if you lost your passport?
- We won't go out unless the weather ___ (improve).
- If he had asked me, I ___ (help) him.
- Fix the mistake: If I will see her, I will tell her.
Show answers
- boils
- rains
- had
- will call
- had left
- wouldn't buy
- would … do
- improves
- would have helped
- If I see her, I'll tell her.
Next step: if you don't know your level, take the English level test (about 15 minutes, with instant results). To keep working on this topic, see Vozi Grammar's English grammar exercises by level.
Frequently asked questions
How many conditionals are there in English?
Four are usually taught: zero (general facts), first (real possibilities), second (imaginary situations) and third (a past that didn't happen). There are also mixed conditionals, which combine the second and the third.
What is the difference between the first and the second conditional?
The first is for something possible (If I get the job, I'll move); the second, for something imaginary or unlikely (If I got the job, I'd move). The tenses change: present + will versus past + would.
Why do we say If I were you and not If I was you?
In the second conditional, were is used with every subject in formal English. If I was you is common in conversation, but were is preferred in exams and formal writing.
Can you use will after if?
In conditionals, usually not: If it rains, I'll stay home. It is only used in special cases, such as polite requests (If you will wait here, I'll call her).