Complex sentence: Thérèse Johanne Alexandra Tietjens (July 17,1831--October 3,1877) was a leading opera and oratorio soprano singer of Hungarian origin who was born in Hamburg, but made her career in London during the 1860s and 1870s.
Split into simpler sentences: Thérèse Johanne Alexandra Tietjens (July 17,1831--October 3,1877) was a leading opera and oratorio soprano singer of Hungarian origin. Born in Hamburg, Germany, she made her career chiefly in London during the 1860s and 1870s.