if-clause type 3 (third conditional)

(Explanation of the conditional sentence type 3 in English)

Table of contents – third conditional sentence

On this page you will find the following:

  1. Use of the third conditional sentence
  2. Form of the third conditional sentence
  3. Further explanations and exercises

When is the third conditional sentence (if-clause type 3) used?

In general, we use conditional sentences for ideas or situations that depend on another. They are, therefore, subject to a condition. In particular, the third conditional sentence, which is also often called if-clause type 3, is used for circumstances that could have occurred due to a condition (in the past) but can no longer occur (in the present). Compare the following use of the conditional 3:

  • Some examples to illustrate the use of the if-clause type 3:
    • “If I hadn’t broken my leg, I would have travelled to South America with you.”
    • “If he had taken the train, he wouldn’t have had a car accident.”
    • “You wouldn’t have lost your job if you hadn’t insulted your boss.”
  • Note: In all three cases, the circumstances (world trip, car accident, and work) would have come true if the condition stated in the if-part had been fulfilled. As this ought to have already happened in the past, the situation described can no longer occur in the present. For help which if-sentence to choose, have a look at the chart of conditionals.

How is the third conditional sentence (if-clause type 3) formed?

Basically, a conditional sentence in English always consists of two clauses. One of them (the subordinate clause) usually starts with the word ‘if’ and specifies the condition while the other one (the main clause) returns the result. Concerning the spelling and clause position, it does not matter which of the two begins the complex sentence; however, in case ‘if’ is at the beginning, a comma must be placed between the two. Continuous or progressive aspect (which is the ing-form) can also be used in both clauses. Consider the details:

Rule for forming the third conditional sentence (if-clause type 3)

‘if’ + past perfect simple or continuous, clause with past conditional simple or continuous

Additional examples

Also, mind the position of the clauses:

  • “If I had had the opportunity, I would have left.”
    • A comma must be inserted because the sentence starts with ‘if’.
  • “If you hadn’t turned off the TV, I would have been watching the match.”
    • This order also requires a comma.
  • “You would have chosen to leave if I had been talking all the time.”
    • No comma needed here as ‘if’ appears in the second part.

Further explanations related to the ‘Third conditional (if-clause type 3)’

The following additional explanations are related to the topic ‘Using the third conditional sentence (if-clause 3)’ and could be helpful too: