The Third Conditional

Form​​ 

We form the third conditional the following way:

 

Main clause

If clause

would have + participle

I would have visited you.

you would have passed the test.

past perfect​​ (continuous)

If I had had the time,

If you hadn’t been partying,

 

If clause

Main clause

past perfect (continuous)

If I had had the time,

If you hadn’t been partying,

would have + participle

I would have visited you.

you would have passed the test.

 

 

2.​​ Meaning

We use the third conditional to talk about​​ a past event​​ which did not happen. With the third conditional, we express how we would like to change the past.

 

 If I​​ had won​​ the lottery last week, I​​ would have bought​​ that sports car.​​ (But I didn’t win​​ the lottery so I didn’t buy that sports car.)

 

 

3. Main clause + modals

It is possible to use​​ could​​ or​​ might​​ instead of would in the main clause of the conditional sentence.​​ 

 

He​​ might have gone​​ to the party if he​​ had been invited.

 He​​ could have met​​ lots​​ of friends if he​​ had gone​​ to the party.

 

 

4. If clause + could

We can use could in the if-clause of the conditional sentence.

 

 If I​​ could have flown​​ to New York yesterday, I would have seen the carnival.