Complex sentence: Archealogical finds in Prussia date a continuous presence back to at least two thousand BC. Baltic people spoke a variety of languages, with Prussian belonging to the western branch of the Baltic language group is no longer spoken.
Split into simpler sentences: Archealogical finds in Prussia date a continuous presence back to at least two thousand BCE. The Baltic people spoke a variety of languages, with Prussian belonging to the western branch of the Baltic language group which is no longer spoken.