Complex sentence: Amanda Woods (Cameron Diaz) owns a company which produces movie trailers with her best friend Miles (Jack Black); she handles editing while he provides incidental score, and scenes concerning her are occasionally accompanied by narration in the voice of Hal Douglas.
Split into simpler sentences: Amanda Woods (Cameron Diaz) with her best friend Miles (Jack Black) owns a company that produces movie trailers. She handles editing while he provides incidental score, and scenes concerning her are occasionally accompanied by narration in the voice of Hal Douglas.