Complex sentence: The largest formation ever was the 400way created and held over Udon Thani, Thailand on February 8,2006 and there is to be a World Record attempt of 444 or greater to be held in January 2011, again in Thailand.
Split into simpler sentences: The largest formation ever was the 400way created and held over Udon Thani, Thailand on February 8,2006. There is to be a World Record attempt of 444 or greater to be held in January 2011, again in Thailand.