电气设备发生火灾时，一般情况下第一步应立即（）
A、选用不导电灭火剂灭火
B、选用黄砂灭火
C、切断火源
D、切断电源
参考答案：D
— Why didn't you come to our party yesterday? There was a lot of fun.
— I _________, but I had an unexpected guest at home.
A. had
B. was going to
C. did
D. would
依据华电集团《电力安全工作规程》在厂区内进行以下（）工作，需填用动土作业票。
A.种植花草树木
B.挖土、打桩等入土深度0.5m以上
C.使用推土机、压路机等施工机械进行填土或平整场地的作业
D.在有地下设施的地方进行土方工程
