Complex sentence: He became mayor of Freiburg on July 1,2002, after receiving 64.4% of votes on the second ballot held May 5,2002, thereby becoming the first Green mayor of a large German city and only the second in the whole of Germany.
Split into simpler sentences: He became mayor of Freiburg on July 1,2002, after receiving 64.4% of votes on the second ballot held May 5,2002. He is the first Green mayor of a large German city and only the second in the whole of Germany.