Simplify the following text for a Grade 8 native English-speaking person.
Original: Button won six of the first seven races of the season and on 18 October at the Brazilian Grand Prix , he secured the 2009 Drivers ' Championship and the team won the Constructors ' Championship .
Simplified: On 18 October 2009 , at the Brazilian Grand Prix , Button won the 2009 Drivers ' Title on his first season for Brawn GP .