Complex sentence: Barry came to national prominence as mayor of the national capital, the first prominent civil rights activist to become chief executive of a major American city; he gave the presidential nomination speech for Jesse Jackson at the 1984 Democratic National Convention.
Split into simpler sentences: Barry came to national prominence as mayor of the national capital, the first prominent civil rights activist to become chief executive of a major American city. He gave the presidential nomination speech for Jesse Jackson at the 1984 Democratic National Convention.