virtual memory

例句：

1. 1. The virtualmemory system is designed to improve the performanceof computer programs.
   虚拟内存系统旨在提高计算机程序的性能。
2. 2. The virtual memory is afeature that allows computers to store data inmemory without physically moving it.
   虚拟内存是一种功能，允许计算机在内存中存储数据而无需物理移动它。
3. 3. The virtualmemory can be used to simulate the behaviorof larger memory systems.
   虚拟内存可以用于模拟更大的内存系统的行为。