Complex sentence: The bill was the signature initiative of activist Dorothea Dix, and passed both houses of congress in 1854, but was vetoed May 3,1854 by president Franklin Pierce, the first of his nine vetoes.
Split into simpler sentences: The bill was the signature initiative of activist Dorothea Dix, and passed both houses of Congress in 1854. However, it was vetoed on May 3,1854 by President Franklin Pierce, the first of his nine vetoes.