Complex sentence: Jablonsky studied composition at the University of California, Berkeley, and worked for seven years for Harry Gregson-Williams at Media Ventures, the music production company which was conceived and founded by Jay Rifkin and Hans Zimmer.
Split into simpler sentences: Jablonsky studied composition at the University of California, Berkeley. Jablonsky has worked for seven years for Harry Gregson-Williams at Media Ventures, the music production company which was conceived and founded by Jay Rifkin and Hans Zimmer.