demand recorder

例句：

1. 1. The demand recorder is essential for recording the data accurately.
   需求记录器对于准确记录数据至关重要。
2. 2.The demand recorder was used to capture the sound of the crowd during the protest.
   需求记录器被用来捕捉抗议活动中人群的声音。
3. 3.The demand recorder was used to document the history of the event.
   需求记录器被用来记录该事件的历史。