Conditionals

If-sentences

Conditional sentences can be split up into two parts: condition (the part that contains 'if') and a result.
1. The sentence can begin with either one:
If you touch this button, the machine will explode.
The machine will explode if you touch this button.
2. You write a comma between the two parts when the sentence begins with the condition:
If I knew the answer, I would have given it.
I would have given the answer if I knew it.

Type Zero Conditional
(if+Present Simple; Present Simple)
(refers to the present or future)
If I spend more than ten minutes in the sun, I get a sunburn.
Every time this condition appears, this result occurs.
Type One Conditional
(if+Present Simple; will+infinitive)
(refers to the present and future)
Traffic is heavy today, if I drive to work, I will be late. I should take the underground.
In case this condition is true, we will get this result.
Type Two Conditional
(if+Past Simple; would+infinitive)
(refers to the present or future)
If it didn't rain today, we could/would go for a walk.
If this condition was true, this result would occur. But the condition is not in place, so the result is not possible.
Type Three Conditional
(if+Past Perfect; would have+Past Participle)
(refers to the past)
If you had studied for the exam, you would have passed.
If this had happened, we would have had that result in the past. But it did not happen, so the result did not take place either..
Mixed Conditionals
A combination between type two and three
1. A past condition with a present result:
If you had studied for the exam, you would be in university now.
2. A present condition with a past result:If he loved her, he would have stayed with her.

If you have seen conditional sentences that are not described here, you can check Conditionals Part 2, where they are described in more detail.

Exercises