The third conditional in English

Do you ever think about how the past might have been different if you’d done something else? If you do, you need to learn the third conditional in English!  

We use the third conditional to talk about things that didn’t happen in the past. The clauses in the third conditional talk about things which are impossible. We haven’t mastered time travel yet, so of course we can’t actually change the past! 

The structure of the third conditional

The third conditional is made of two clauses: the conditional clause and the main or result clause. The structure of a sentence in the third conditional is: 

The structure of the past perfect is had + past participle. Remember, the past participle is the third form of the verb e.g., give – gave – given, or want – wanted – wanted. 

• If I had studied harder, I would have passed the exam. 

We can change the order of the clauses without changing the meaning. If the main clause comes first in the sentence, we don’t need a comma. 

• I would have passed the exam if I had studied harder.

Examples of the third conditional

We can use both positive and negative clauses in the third conditional. Have a look at these examples: 

• If you had gone to bed earlier yesterday, you would not have had such trouble waking up this morning. (But you did not go to bed early, and you did have trouble waking up.)
• Sara would not have hired Alice if she had known how lazy she is.
• I would have remembered if you had told me. 

Other modal verbs in the third conditional

We can replace would with other modal verbs in the result clause of the third conditional. We can use the verbs could and might. The structure remains the same: could / might have + past participle. We use could to say that something would have been possible. We say might if we’re not sure what would have happened. 

Here are some examples: 

• If it had been sunny yesterday, we could have gone to the park. 
• I could have come earlier if you had called me. 
• If I had worked harder at university, I might have graduated with a better degree. 
• Dave might not have got a fine if he had apologised. 

If only…

We can use the phrase if only instead of simply if to express a very strong desire that something had been different.  

• We would have won the game if only you had scored that goal. 
• If only I had taken the train instead of driving to the airport, I wouldn’t have missed the flight. 

The second vs. the third conditional

Learners often get confused between second and third conditional sentences. Remember, we can only use the third conditional to talk about the past. We use the second conditional to hypothesise, or imagine, about the present or the future. Compare these sentences in the second and third conditional:

• If it was sunny, I would go for a walk. (Now!)
• If it had been sunny, I would have gone for a walk. (In the past!)

• Tom would buy a house if he had more money. (Now!)
• Tom would have bought a house if he had had more money. (In the past!)
  • ! Seeing had had together often looks very wrong to learners. It’s not wrong, it is the past perfect form of have. If we’re speaking, we’re more likely to say if he’d had… !

The third conditional has past participle verbs in both clauses. The second conditional does not contain any past participles. 

The zero conditional in English

Interesting third conditional questions

We can use the third conditional to ask interesting questions about people. You can learn about their wishes and desires for the past, as well as their regrets. Here are some examples: 

• If you could have grown up anywhere in the world, where would you have chosen?
  • What would have been different about your life? 
• If you hadn’t chosen the career you did, what would you have done instead?
• What’s the most important piece of advice you have ever received? 
  • How would your life have been different if you hadn’t received that advice?

How would you answer these questions?