Tian'anmen Building is the place ________ Chairman Mao Zedong announced that our P. R. C. was founded.

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Oct. 1, 1949 is the day ________ I will never forget.

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Oct. 1, 1949 is the day ________ our P. R. C. was founded.

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It was a meeting ________ importance I did not realize at that time.

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________ environmental damage is done, it takes many years for the ecosystem（生态系统）to recover.

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________ by a greater demand for vegetables, farmers have built more green houses.

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When you get the paper back, pay special attention to what ________.

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You are lucky enough to escape ________ after making such a mistake.

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A man in his twenties broke into a bank early this morning, which was seen by people working in the shop ______ who heard the breaking of glass.

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With April 18's railway speedup, highway and air transport will have to compete with ________ service for passengers.

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