Complex sentence: The service began broadcasting 4 December 2006 merging the news assets of the two former sub-regions, and its newsrooms were officially opened on 26 January 2007 by ITV executive chairman, Michael Grade.
Split into simpler sentences: The service began broadcasting 4 December 2006, when the news operations of the two regions were merged into a single entity. ITV Thames Valley's newsrooms were officially opened on 26 January 2007 by ITV executive chairman, Michael Grade.