Если бы Боб поехал в аэропорт вовремя, он бы не опоздал на самолет.
If Bob has gone to the airport in time, he would not have missed the plane.
If Bob had gone to the airport in time, he would not have missed the plane.
If Bob went to the airport in time, he would not have missed the plane.
If Bob have gone to the airport in time, he would not have missed the plane