Complex sentence: It is the largest town of the wider Borough of Boston local government district which had a total population of 64,600 at the 2011 census whilst the town had a population of 35,124 at the 2001 census.
Split into simpler sentences: It is the largest town of the wider Borough of Boston local government district. The borough had a total population of 64,600 at the 2011 census, whilst the town itself had a population of 35,124 at the 2001 census.