钢铁是使用最多的金属材料，但每年因锈蚀而损失的数量巨大，防止

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钢铁是使用最多的金属材料，但每年因锈蚀而损失的数量巨大，防止金属腐蚀已成为科学研究中的重大问题．以下有关金属腐蚀的叙述不正确的是（　　）

A．钢铁在潮湿的空气中比在干燥的空气中更易锈蚀

B．钢铁锈蚀的实质是铁与空气中的氧气、水蒸气等发生了化学反应

C．铝比钢铁中的铁活泼，因而铝的抗腐蚀性能比钢铁差

D．在钢铁表面刷漆或镀耐腐蚀金属都可防止钢铁锈蚀

答案

答案：C

完形填空

When I first entered university, my aunt, who is an English professor, gave me a new English dictionary. I was   1  to see that it was an English English dictionary, also known as a monolingual（单语的） dictionary.   2  it was a dictionary intended for non-native learners, none of my classmates had one and, to be honest, I found it extremely 3  to use at first. I would look up words in the dictionary and still not fully understand the meaning. I was used to the   4  bilingual（双语的）dictionaries, in which the words are    5  both in English and Chinese. I really wondered why my aunt   6  to make things so difficult for me. Now, after studying English at university for three years, I   7 that monolingual dictionaries are  8 in learning a foreign language.
As I found out, there is in fact often no perfect equivalence(对应) between two 9  in two language. My aunt even goes so far as to 10 that a Chinese “equivalent” can never give you the   11 meaning of a word in English! Therefore, she insisted that I read the definition(定义) of a word in a monolingual dictionary when I wanted to get a better understanding of its meaning. 12  , I have come to see what she meant.
Using a monolingual dictionary for learners has helped me in another important way. This dictionary uses a(n)   13  number of words, around 2, 000, in its definitions. When I read these definitions, I am 14 exposed to the basic words and learn how they are used to explain objects and ideas. 15 this, I can express myself more easily in English.

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根据DL5009.1—2014《电力建设安全工作规程第1部分：火力发电》第7.4.4条规定，受电及带电试运行停电作业时应符合下列规定（）

A.执行操作票制度，不宜带负荷拉合隔离开关

B.运行中的星形接线设备的中性点应视为带电设备

C.电气设备停电时应将各路电源完全断开

D.严禁在只经开关断开电源的设备上作业，作业时应至少有一个明显的断开点

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