Simplify the following text for a Grade 12 native English-speaking person.
Original: There were further changes to try to improve the on-track spectacle with the return of slick tyres , changes to aerodynamics and the introduction of Kinetic Energy Recovery Systems ( KERS ) presenting some of the biggest changes in Formula One regulations for several decades .
Simplified: Several rule changes will be implemented by the FIA , in a bid to cut costs due to the global financial crisis and to improve the on-track spectacle . New rules governing tyres , aerodynamics and Kinetic Energy Recovery Systems ( KERS ) , among others , are some of the biggest changes in the Formula One regulations for several decades .