Pedro, I happened to do this in class last week.
Inversion replacing
“if” in conditional sentences
You can use inversion to replace if in conditional
sentences that include should, were or had:
Should you need any help with your bags, please let me
know.
Were you to stop messing around with your mobile
phone, you might learn a bit more.
Had you not tried to do three things at once, this
would never have happened.
With “had”
1. If she had not helped me I would have been in bad
trouble.
2. If it had not rained yesterday, we would have had
the party in the garden.
3. If you hadn’t been so stupid as to reject that job
offer, you would not have these worries now.
With “should” (it has no meaning of
obligation!)
5. If you do not wish to join them, you must let them
know soon.
6. If you decide to sell the house, I will be happy to
buy it.
With “were”
(to talk about imaginary future situations)
7. If we were to have kids, we would need a bigger
house.
8. If he was not so lazy, he would have passed his
exams.
9. If she was older, we would let her go on the trip.