Conditionals in English

2,410 fill-in-the-gap exercises across 5 forms

Five patterns for saying what depends on what. Each one fixes the tense in both halves of the sentence.

If the condition

she had studied if-clause

she the result

would have passed main clause

Pick a form to practice

First Conditional 580 sentences, 58 tests of ten Mixed Conditionals 480 sentences, 48 tests of ten Second Conditional 450 sentences, 45 tests of ten Third Conditional 450 sentences, 45 tests of ten Zero Conditional 450 sentences, 45 tests of ten

Two halves. One states a condition, the other states what follows:

If it rains, we’ll stay in.

Either half can come first. When the if half leads, a comma separates them; when it follows, no comma:

We’ll stay in if it rains.

Will and would never appear in the if-clause. Whatever the type, the tense in the if half is one step further back than you would expect:

Get that right and most conditional errors disappear.

Ask two questions: is this real, and when is it?

Always true? → zero. If you heat ice, it melts.
Might really happen? → first. If I finish early, I’ll call you.
Not true now, or unlikely? → second. If I spoke Japanese, I’d apply.
Already over, cannot be changed? → third. If we had left earlier, we’d have caught it.
Past cause, present result? → mixed. If I hadn’t missed the train, I’d be home by now.

Unless means if not, and takes the same tenses:

I won’t go unless you come with me.

As long as, provided that and in case work the same way. None of them takes will either.

In the second conditional, formal English uses were for every subject:

If I were you, I’d wait.

If I was you is common in speech but were is what tests expect, and the phrase if I were you is fixed.

Type	If-clause	Main clause	Used for
zero	If you heat water	it boils	things that are always true
first	If it rains	we will stay in	a real future possibility
second	If I had time	I would help	unreal or unlikely now
third	If she had asked	I would have helped	the past, which cannot change
mixed	If she had asked	I would be there now	past cause, present result

Wrong: If it will rain, we will stay in. correct: If it rains, we will stay in.

Will never goes in the if-clause. The present tense carries the future meaning.

Wrong: If I would have known, I would have called. correct: If I had known, I would have called.

The if-clause of a third conditional takes had plus the past participle, not would have.

Wrong: If she had studied, she would passed. correct: If she had studied, she would have passed.

The result half needs would have plus the past participle.