厂站内在无需高压设备停电或做安全措施配合的二次系统、动力等回路上的工作。需选用厂站第一种工作票。（）
参考答案：错
____ by his teachers, he felt nervous. [ ]
A. Having watched
B. Having been watching
C. Watching
D. Being watched
窗口事件是指操作窗口时所引发的事件，下列不属于窗口事件的是______。
A) 打开 B) 关闭 C) 加载 D) 取消
