Adverb:

1. for life;

   "desire happiness in perpetuity"
   "an annuity paid in perpetuity"
   

2. for an indefinitely long time;

   "bequeathed to the nation in perpetuity"
   

inprep.在 ... 里；在 ... 地方；在 ... 期间；在 ... 方面；进入...里面；处于...状态；穿着...；以...的方式adv.在家；入；进；向里；在某地；并入；在某种关系中adj.在里面的；新来的；执政的；<口>时髦的n.当权者；影响；达成目标的路径Inzerra因泽拉

1. The land was given to him in perpetuity.
   这土地永远归他所有了。
2. This terrible event is etched forever in my memory.
   这一可怕事件永远深深地印刻在我的记忆中。