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【多选题】
当UPS交流输入中断时，逆变器无法逆变，查找缺陷（）？A.
检查旁路电源是否正常
B.
测量直流输入电压，因为若直流输入电压过低，控制电路检测到直流电压过低信号后，就会中断逆变电路工作
C.
检查辅助电源是否正常，逆变驱动管有无损坏
D.
检查输出保护电路
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皮皮学刷刷变学霸
举一反三
【多选题】What information are supposed to be in the introduction section in the report?
A.
Background
B.
Summary of the results and conclusion
C.
The purpose of the research
D.
The research method
【判断题】The topic sentences in the body paragraphs link body paragraphs with the thesis statement in the introduction.
A.
正确
B.
错误
【简答题】Why introduction is important in the negotiation? What should be included in the introduction?
【单选题】---She isn't a teacher, is she? ---_______.
A.
Yes, she isn't
B.
Yes, she is
C.
No, she is
D.
I think she is
【简答题】建筑工程项目具有明确的建设目标,包括( )目标和( )目标。
【简答题】In introduction, the first part should be the background information which serves as a lead-in; the second part should be the ( );the last part is the thesis statement and structure.
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