A female dolphin has a baby every two to three years. She gives birth to the baby under water.

雌海豚每两至三年生一个孩子。她是在水下产婴的。

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Pandas are notoriously fussy when it comes to finding mates. Females in the wild normally have a cub once every two to three years, and the fertility of captive giant pandas is even lower.

大熊猫寻找伴侣时非常挑剔，野生雌性大熊猫每隔两三年生一只幼仔，圈养大熊猫的繁殖率就更低了。

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Most manufacturers recommend divers to have their diving watch pressure tested by an authorized service and repair facility annually or every two to three years and have the seals replaced.

大局部的制造商建议潜水员到授权机构停止潜水表压力测试并且每年或两到三年修缮一次潜水表的零件，以及改换密封件。

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"Military folks move every two years generally, two to three years, and so that turnover and that constant influx of buying houses,buying cars, buying clothes for schools, is just a huge impact to the Enterprise community."

VOA: standard.2010.08.10

And you have the update problem, where people replace their computers every two to three years, whereas its six to eight years for TV.

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Joy of joys, after the next film is released, there will be a new Star Wars film every two to three years after that.

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We plan to release the first new Star Wars film in 2015, and then plan to release one film every two to three years.

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