交流采样有功二次进线，如果B、C相电压进线对调，会造成该有功遥测值很小。
参考答案：对
My grandma fell asleep while she ______ TV last night. [ ]
A. watches
B. watched
C. was watching
D. has watched
人免疫缺陷病毒属于（）
A.单链DNA病毒
B.双链DNA病毒
C.单链RNA病毒
D.双链RNA病毒
E.缺陷型病毒
