在过去十八年的每个月中，马西博士都会接受恒星“55Cancri A”发出的讯号。逐渐地，“正弦波”曲线出现明显的分离。

Every month for the past 18 years, he has tuned in to the signal coming from 55 Cancri A. Gradually, the separate sine waves have become visible.

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报告指出，在过去十八年间，已有四十九座新城市被建立。

The report says 49 new cities have been built in the past 18 years.

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例如，一直生长在北美的加拿大雌鹅在过去的十八年里增加了300% ，达到了400 万只。

For example, permanent populations of Canada geese in North America have increased three hundred percent in eighteen years to four million birds.

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例如，一直生长在北美的加拿大雌鹅在过去的十八年里增加了300% ，达到了400 万只。

For example, permanent populations of Canada geese in North America have increased three hundred percent in eighteen years to four million birds.

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