permanence

n.永久，持久

periscope, periscopic, perish, perishable, perishables, perished, perisher, perishing, peristyle, peritonitis, periwinkle, perjure, perjurer, perjury, perk, perkily, perkiness, perky, perm, permafrost, permanency, permanent, permanent wave, permanent way, permanently, permanganate, permeability, permeable, permeate, permeation, permissible, permissibly, permission, permissive, permissively, permissiveness, permit, permutation, permute, pernicious,