series excited motor

例句：

1. 1. This is a sequence of steps to follow.
   这是一系列要遵循的步骤。
2. 2.The series of events led to the discovery of the cure.
   一系列事件导致了发现治愈方法。
3. 3.The museum has a series of exhibits on ancient civilizations.
   博物馆有一系列关于古代文明的展品。