Conditionals in English

Overview: The 5 English Conditionals

There are 5 main conditionals in English: the zero, first, second, third and mixed conditional. We use them to talk about facts, real possibilities, imaginary situations and how the past could have been different.

A conditional sentence is normally in two parts:

• the if-clause (the condition)
• the result clause (what happens if that condition is true)

We can put the if-clause first or second. If it comes first, we usually use a comma to separate the two parts:

If it rains, I'll stay at home.
I'll stay at home if it rains.

Zero Conditional – Facts & General Truths

The zero conditional is used for things that are always true, general rules and habits. Both parts of the sentence are usually in the present simple.

Form: If + present simple, present simple

Examples:

• If I go to McDonald's, I always get a Big Mac. (I always do this.)
• When it rains, I wear my waterproof jacket.
• If it rains, the grass gets wet. (A fact.)

We can also use when instead of if when something is always true.

First Conditional – Real Future Possibilities

The first conditional is used to talk about things that are likely to happen in the future. One part of the sentence is in the present simple and the other part is usually in the future with will, or sometimes might.

Form: If + present simple, will/might + base verb

Examples:

• If it's sunny tomorrow, we'll go to the beach.
• I won't go to the cinema if it rains.
• If he gets away from work earlier, we might go to the beach.

Common mistake: students often say “If I will go…”. This is wrong. We say:

If I go, I'll call you. ✅
If I will go, I'll call you. ❌

Second Conditional – Advice & Imaginary Situations

The second conditional is used for imaginary / hypothetical situations in the present or future, and also to give advice. One part of the sentence is in the past simple, and the other part usually has would (or could / might) + base verb.

Form: If + past simple, would/could/might + base verb

Examples:

• If I were you, I'd go to the doctor. (Advice.)
• If I won the lottery, I'd buy a house. (Imaginary future.)
• If you were a monkey, you could climb that tree. (Imaginary present.)

Note: After modal verbs like would / should / could / might, we do not use to:

If I won, I would buy a car. ✅
If I won, I would to buy a car. ❌

Third Conditional – Imagining a Different Past

The third conditional is used to imagine how the past could have been different. We often use it to talk about regrets or complaints.

The if-clause uses the past perfect, and the other part uses a modal verb (usually would) + have + past participle (3rd form).

Form: If + had + past participle, would/could/might + have + past participle

Examples:

• If I hadn't downloaded Skype, I wouldn't have opened this file. (Both actions happened.)
• If I hadn't cheated on my wife, she wouldn't have left me.
• If I'd seen him, I'd have talked to him. (Neither action happened.)

Important: when we use the negative form in the third conditional (hadn't / wouldn't have), it usually means the thing actually happened in real life.

Also, don't be afraid of had had – in spoken English we usually use a contraction:

If I'd had a 10 pound note, I would have paid for the taxi.

Mixed Conditional – Past Cause, Present Result

The mixed conditional is used to show how something in the past affects the present. The if-clause is like the third conditional (past perfect), and the result clause is like the second conditional (would + base verb).

Form: If + had + past participle, would + base verb

Examples:

• If we hadn't won the war, we would be reading this in German.
• If I hadn't asked that girl to dance, we wouldn't be married now.

Punctuation Tip

To separate the two parts of a conditional sentence we use a comma only when the sentence starts with if:

If it rains, we'll stay in. ✅
We'll stay in if it rains. ✅ (no comma)

This is important for written English, but you don't hear the comma when speaking, of course.