As in a free labor system and unlike slavery, the overlords had no responsibility for the serf's maintenance and no direct interest in his or her survival as an expensive piece of property.

与自由的劳动力体制一样但与奴隶制不同，农奴主对于农奴的生存没有任何责任，对于这样一件昂贵的财产的死活也没有直接的兴趣。

Slavery is the system by which some people are owned by others as slaves.

当今美国的黑人拥有平等权在某种程度上也是他们的成就。