电气工具和用具应由()保管,每6个月应由电气试验单位进行()检查。
参考答案:专人;定期
西周末年,昏庸的周幽王上演了一场“烽火戏诸侯”的闹剧。诸侯率兵前往护卫周王是遵守了 ( )
A.封建制的法规
B.禅让制的规则
C.世袭制的传统
D.分封制的义务
Mr. White stayed with my father for two months _______ time he drank all the wine that my father had.[ ]
A. at which
B. in that
C. on which
D. during which