Complex sentence: Prosecutors called it a shell corporation set up primarily so Castroneves could dodge US income taxes, but Castroneves'father testified he created Seven to boost his son's image in Brazil.
Split into simpler sentences: Prosecutors called it a shell corporation set up primarily so Castroneves could dodge U.S. income taxes. Helio Castroneves Sr., Helio's father, however, testified that he created Seven to boost his son's image in Brazil.