Complex sentence: This double control mechanism of 32 counties plus 10 counties corporate remained unchanged for a little over two centuries until the early 19th century, since when counties have been adapted and in some cases divided by legislation to meet new administrative and political requirements.
Split into simpler sentences: This double control mechanism of 32 counties plus 10 counties corporate remained unchanged for a little over two centuries. Since the early 19th century, counties have adapted by legislation to meet new administrative and political requirements.