用手工TIG焊焊接铝、镁及其合金时,采用()最佳。
A、直流正极性
B、直流反极性
C、交流电源
参考答案:C
—I called you yesterday afternoon, but there was no reply.
—I ______ a dolphin show in the zoo with my cousins. [ ]
A. watched
B. will watch
C. am watching
D. was watching
医疗机构从业人员行为规范适用人员包括()。
A.管理人员
B.医护人员
C.药学技术人员与医技人员
D.其他人员
E.以上都是