他积极参加政治活动，强烈反对奴隶制度。 He was active in politics and was strongly against slavery.
我的最高目标是拯救美国，摧毁奴隶制度。 My paramount object is to save the union and destroy slavery.
美国南北战争以前，要废除奴隶制度是因难的，因为维持这一制度的人有既得利益。 It was difficult to end the system of slavery before the Civil War because the people who owned the slaves had a vested interest in keeping it.