________ was regarded as impossible has now become a reality.

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I could appreciate it ________ you call back this afternoon for the doctor's appointment.

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________ around Tian'an men Square, the tourists were taken to visit the Palace Museum.

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Equipped with modern facilities, today's libraries differ greatly ________.

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I didn't manage to work out the problem ________ the teacher had explained now.

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You're not allowed ________ notices on this wall without special permission.

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The problem ________ we should put off the sports meet ________ at the meeting yesterday.

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--Was the test difficult?

--Not at all. We found ________.

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I follow my own opinion, not hers in questions of this kind, ________ of course makes her unhappy.

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The passenger was tired and walked more slowly but he got home ________.

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