How do you write the passive voice in unreal conditional sentences?
If ... were ..., ... would be ....
If ... had been ..., ... would have been ....

If the spy were seen with you, he would be shot.
If the spy had been seen with you, he would have been shot.

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if one gram of any element were completely converted into energy, it would release the same amount of heat as the BURNING OF 1500000 TONS OF COAL.

if the gold had been bought by me i would have been rich by now