收藏家收藏清末铝制品，至今保存十分完好，该艺术品不易锈蚀的主要原因是（　　）

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    I am studying in a new school now. My old school was smaller and older than this new one. It was only l, 300 square metres. The buildings were lower, too. And there was less grass and trees. It had six grades and about 200 pupils and teachers. The number of the students in the news chool is much bigger than the old one. In my old school, the class began from eight to eleven thirty in the morning. I had lunch at school and then I had class from one to three in the afternoon. I had less homework and more rest time in my old school. But I can learn more in the new school. What about your school?

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