Complex sentence: Karl Friedrich Adolf Boser (1811, at Halbau in Prussian Silesia--1881 at Dusseldorf), studied in Dresden, Berlin, and Düsseldorf; his paintings, chiefly genre subjects and portraits, were popular.
Split into simpler sentences: Karl Friedrich Adolf Boser (1811, at Halbau in Prussian Silesia--1881 at Dusseldorf), was a German artist. He studied in Dresden, Berlin, and Düsseldorf; his paintings, chiefly genre subjects and portraits, were popular.