sentence: Not all manors had all three kinds of land: as an average, demesne accounted for roughly a third of the arable area and villein holdings rather more; but some manors consisted solely of demesne, others solely of peasant holdings.
modified: fix grammar: Not all manor had all three kind of lands: as an average, demesnes accounted for roughly a thirds of the arable areas and villeins holding rather more; but some manor consisted solely of demesnes, other solely of peasants holding.