翻译

段落

A major disadvantage of mass storage systems is that they typically require mechanical motion and therefore require significantly more time to store and retrieve data than a machine’s main memory ,where all activities are performed electronically.
  大容量存储系统的一个主要缺点是，它们通常需要机械运动，因此存储和检索数据所需的时间比机器的主存储器要长得多，因为机器的所有活动都是以电子方式执行的。