If I’d seen Poppy,
I wouldn’t have fallen over.
If you'd remembered the map,
we wouldn’t have got lost.
If I'd known it was your birthday,
I would've bought you a present.
If they hadn't won the match,
the manager would've lost his job.
If the train hadn't stopped in time,
there would've been a serious accident.
If you hadn't been so lazy,
you wouldn't have failed the exam.
'If' clause
past perfect
Main clause
would have + past participle
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