A Quick Guide to Third Conditional

Mastering the third conditional often presents a challenge to a lot of students. By following this brief guide, you will get a general overview of the crucial grammatical points and tackle the most challenging aspects of the III conditional type. Also, check out the English courses offered by grade.ua if you want to get a better grasp of English grammar.

Formation and Structure

The third conditional, also referred to as type III if-clause, is used to imagine hypothetical or unreal situations in the past. The type III if-clause focuses on the past instead of the present or future and is used to depict an alternative version of the past that, under specific conditions, may have happened.

The conditional sentence usually consists of two parts: the if-clause, which indicates a hypothetical past situation using the past perfect, and the main clause, which expresses the hypothetical past outcome using the modal perfect verb plus the past participle.

Here’s the general structure of the third conditional:

if-clause main clause
If + Past Perfect could/would/should + have + past participle
If I had studied harder, would have passed the exam.
If I had locked the car, it wouldn’t have been stolen.
If you had asked me, could have helped you buy the tickets.


The third conditional can be used in a wide range of situations, which typically include:

1) Regret (wishing that something went differently in the past)

If I had studied medicine, I would have become a cardiologist.

2) Imagining alternative past situations

If I had gone to Australia, I could have visited the Great Barrier Reef.

3) Criticism

If you had gone to bed earlier, you wouldn’t have missed the bus.


One can use an if-clause at the beginning or the end of a sentence. When an if-clause comes first, it must be separated by a comma.

If I had been smarter, I would have invested in Apple!

If the sentence begins with the main clause, you don’t need a comma. Here’s an example of an if-clause at the end of the sentence.

This party would have been amazing if you had invited that famous singer.