In this usage, we have a past condition (the conditional clause refers to the past) with a present result (the main clause, or result clause refers to the present). We use the Past Perfect Simple to show that the condition is in the past.
If we had finished the reports on time, we wouldn’t have to do them now.
If we had finished the reports in time, = the conditional clause
we wouldn’t have to do them now. = the main clause (result clause)
If he hadn’t missed the flight, he would be in Warsaw now.
If things had gone according to plan, we would have more resources at our disposal.
If you had chosen a different field or study, what would you be right now?
It is also possible to invert the clauses by putting the main clause before the conditional clause to add variety and also when we want to emphasise a certain part of the sentence.
So, we can also use the following structure:
*NOTE: When the main clause comes before the conditional clause, we do not use a comma before the conditional clause.
Compare the following examples with the sentences above:
We wouldn’t have to do the reports now If we had finished them on time.
He would be in Warsaw now If he hadn’t missed the flight.
We would have more resources at our disposal if things had gone according to plan.
What would you be right now if you had chosen a different field or study?
We can use modal verbs in the main clause instead of would / wouldn’t.
– use might / may / could to show uncertainty.
If I had worked harder at school, I may have had a better job now.
– use could / could have been able to to talk about ability.
If he wasn’t allergic to dogs, he could have babysat Sparky.
– use should when you want to talk about something that is advisable or probable.
If you knew I was free, you should have come over.