If I had studied more, I would have passed the exams - Se eu **tivesse estudado mais, eu teria passado a prova.
If A had happened, B would have happened.
The third conditional is used to talk about something that did not happen in the past and to imagine a situation if the past had happened differently.
If + past perfect, modal + have + past participle.
|Lots of examples, how to construct and a pronunciation tip.||BBC Learning|
|Examples and a tip about when to use the second or third conditional.||TeacherIHaveAQuestion|