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问题 问答题 简答题

供电系统状态如何分类？

答案

参考答案：

1、供电状态

供电状态是指用户随时可从供电系统获得所需电能的状态。

2、停电状态

停电状态是指用户不能从供电系统获得所需电能的状态，包括与供电系统失去电的联系和未失去电的联系。对用户的不拉闸限电，视为等效停电状态。自动重合闸重合成功或备用电源自动投入成功，不应视为对用户停电。

填空题

从下面方框中选出10个单词，并将其正确形式填写在答题卡相应题号的位置上，使短文意思正确通顺（每词限用一次）。

A calligrapher (书法家) taught handwriting. One of his students often practiced handwriting with old pieces of newspapers. He _小题1:_______ that he made very little progress _小题2:_______ he had learned for a long time. His teacher said to him, “Why not try _小题3:______ the best paper. Maybe you'll write _小题4:_____.”

The student did as he _小题5:________.It really worked. He made progress not long afterwards and felt _小题6:________.He asked his teacher about the _小题7:________.The calligrapher answered, “When you used old newspapers to practice handwriting, you would think you were writing a draft(草稿). It didn't _小题8:_______ if you wrote badly. Maybe you thought there were plenty of old newspapers to use. In that case you wouldn't pay much _小题9:_________to it. Now you use the best paper and you'll treasure it. Each time you write you feel strongly about the rarity (稀少)of chances and you'll devote all your heart and soul; you'll do the handwriting much more carefully than practicing. Of course you've _小题10:_______ rapid progress.”

Every day of our life is something new. Let us take every day as a piece of the best paper.
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填空题

如图所示的两种剪刀，正常使用时属于省力杠杆的是_____剪刀（填甲、乙）；如图所示，是表示人肱二头肌收缩使前臂曲肘的情况，图中已标出了支点的位置，桡骨及茶杯的受力方向。从图上可知人的前臂是一个            杠杆（选填“省力”、“费力”或“等臂”），这种结构给人带来的好处是                                 。
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