simulator compiler

例句：

1. 1. The simulator is used totest the performance of the software.
   模拟器用于测试软件的性能。
2. 2. The simulator wasdeveloped to help us understand the workingsof the machine.
   模拟器被开发出来，以帮助我们理解机器的工作原理。
3. 3. Thesimulator allowed us to test the newsystem before it was released.
   模拟器让我们在系统发布之前对其进行了测试。