Simplify the following text for a Grade 6 native English-speaking person.
Original: On the other hand , if he chose to dispose of a parcel of land , the serf or serfs associated with that land went with it to serve their new lord . Further , a serf could not abandon his lands without permission , nor could he sell them .
Simplified: In many cases , serfs had to get permission from their lord to marry someone who was not a serf for that lord .