Simplify the following text for a Grade 8 native English-speaking person.
Original: After Rattle relinquished his posts with the CBSO , the Finnish conductor Sakari Oramo became chief conductor in 1998 , and music director in 1999 .
Simplified: After Rattle gave up his job with the CBSO in 1998 and the Finnish conductor Sakari Oramo became chief conductor that year , and music director in 1999 .