【判断题】
对称的三相电源是由振幅相同、初相依次相差120°的正弦电源，连接组成的供电系统。
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因闻到焦臭味而停止运行的电动机，必须找出原因后才能再通电使用。
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低压绝缘材料的耐压等级一般为500V。
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静电现象是很普遍的电现象，其危害不小，固体静电可达200kV以上，人体静电也可达10KV以上。
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用钳表测量电动机空转电流时，不需要档位变换可直接进行测量。
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为安全起见，更换熔断器时，最好断开负载。
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通用继电器是可以更换不同性质的线圈，从而将其制成各种继电器。
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在采用多级熔断器保护中，后级熔体的额定电流比前级大，以电源端为最前端。
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测量交流电路的有功电能时，因是交流电，故其电压线圈、电流线圈和各两个端可任意接在线路上。
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可以用相线碰地线的方法检查地线是否接地良好。
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对绕线型异步电机应经常检查电刷与集电环的接触及电刷的磨损，压力，火花等情况。
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概率为50%时，成年男性的平均感知电流值约为1.1mA，最小为0.5mA，成年女性约为0.6mA。
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停电作业安全措施按保安作用依据安全措施分为预见性措施和防护措施。
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RCD的额定动作电流是指能使RCD动作的最大电流。
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测量电机的对地绝缘电阻和相间绝缘电阻，常使用兆欧表，而不宜使用万用表。
【判断题】
正弦交流电的周期与角频率的关系互为倒数的。
【判断题】
在三相交流电路中，负载为星形接法时，其相电压等于三相电源的线电压。
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220V的交流电压的最大值为380V。
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当导体温度不变时，通过导体的电流与导体两端的电压成正比，与其电阻成反比。
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基尔霍夫第一定律是节点电流定律，是用来证明电路上各电流之间关系的定律。
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《中华人民共和国安全生产法》第二十七条规定：生产经营单位的特种作业人员必须按照国家有关规定经专门的安全作业培训，取得相应资格，方可上岗作业。
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取得高级电工证的人员就可以从事电工作业。
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企业、事业单位的职工无特种作业操作证从事特种作业，属违章作业。
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二氧化碳灭火器带电灭火只适用于600V以下的线路，如果是10KV或者35KV线路，如要带电灭火只能选择干粉灭火器。
【判断题】
在爆炸危险场所，应采用三相四线制，单相三线制方式供电。
【判断题】
当电气火灾发生时首先应迅速切断电源，在无法切断电源的情况下，应迅速选择干粉、二氧化碳等不导电的灭火器材进行灭火。
【判断题】
漏电开关跳闸后，允许采用分路停电再送电的方式检查线路。
【判断题】
用电笔检查时，电笔发光就说明线路一定有电。
【判断题】
高压水银灯的电压比较高，所以称为高压水银灯。
【判断题】
在没有用验电器验电前，线路应视为有电。
【判断题】
使用手持式电动工具应当检查电源开关是否失灵、是否破损、是否牢固、接线不得松动。
【判断题】
电工刀的手柄是无绝缘保护的，不能在带电导线或器材上剖切，以免触电。
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【单选题】
___He teaches physics in a school.
A. What does your father do?
B. Who is your father?
C. What is your father doing?
D. Where is your father now?
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— Excuse me, how much is the jacket?___ It's 499 Yuan.
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A. Yes, you may borrow.
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— Thank you for inviting me.___
A. I really had a happy time.
B. Oh, it's too late.
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— May I see your tickets, please?___
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— Please help yourself to the seafood.___
A. No, I can't.
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【单选题】
— Would you like to go to the concert with us this evening?___
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— Congratulations! You won the first prize in today's speech contest.___
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【单选题】
— How was your trip to London, Jane?___
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C. How did that happen?
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— This box is too heavy for me to carry it upstairs.___
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— Is it possible for you to work late tonight？___
A. I like it.
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— Unbelievable! I have failed the driving test again!___ This is not the end of the world.
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B.
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Are you feeling better today, Jack?___
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C. Yes, thank you, doctor. But I still don't feel good.
D. Don’t worry about me.
【单选题】
Thank you so much for your lovely gift.___
A. Never mind.
B. I'm glad you like it.
C. Please don't say so.
D. No, It's not so good.
【单选题】
Would you like something to drink? What about a cup of tea?___
A. No, thanks.
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A. Not at all.
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C. Nothing serious.
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Good morning, John. How are you doing?___
A. I'm pleased
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C. Not so bad. And you?
D. How do you do?
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How do you do?___
A. Fine, thank you.
B. How do you do?
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D. Very well.
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Good-bye for now.___
A. The same to you.
B. That's OK
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Hello, how are you?___
A. Hello, how are you?
B. How do you do?
C. Fine, thank you.
D. That's OK.
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I didn't mean to do that. Please forgive me。___
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Thank you for your invitation.___
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What a beautiful dress you have on today!___
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D. Thank you.
【单选题】
I think he is a good lecturer.___
A. Sorry, it doesn’t matter.
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— What's the matter, dear?___
A. I didn't go to school.
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Let me introduce myself. I'm Steward.___
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What does Tom's wife do for a living?___.
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