Complex sentence: After a second race at Fuji in 2008, the race returns to Suzuka in 2009 and will continue to alternate between the circuits, owned by perennial rivals Toyota and Honda, respectively.
Split into simpler sentences: After a second race at Fuji in 2008, the race returns to Suzuka in 2009. The Japanese Grand Prix was supposed to continue alternating between Fuji Speedway and Suzuka Circuit, owned by perennial rivals Toyota and Honda, respectively.