Complex sentence: He played a key role in rescuing New York from fiscal crisis in the 1970s, helping the City secure necessary financing when it was on the verge of financial collapse, and assisted in the government bailout of Chrysler in 1980.
Split into simpler sentences: He played a key role in rescuing New York from fiscal crisis in the 1970s, helping the City secure necessary financing when it was on the verge of financial collapse. In 1980, Rosen assisted in the government bailout of Chrysler in 1980.