In 1930 and 1932, Einstein made two more trips to the United States. The first was just a working visit, but the second was because Princeton University offered him a position. This part-time professorship required Einstein to spend seven months each year in Berlin and work five months in Princeton. Einstein accepted the position at Princeton and left Germany in December 1932. However, Einstein did not realize that he would never return to this place for the rest of his life.