Even with the ever-increasing human lifespan, that would likely mean the rest of their mortal existences.

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Instead of assimilating, the two ethnic groups continued to lead largely separate existences, with little inter-marriage.

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While we're no stranger to companies having multiple brands to serve different markets, such as Acer's Gateway and Packard Bell divisions, they usually have the courtesy of acknowledging each other's existences and presenting a coherent strategy.

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This belief gives rise to a duality, where practical and creative endeavors lead largely separate existences -- one slogged at during the workweek and the other indulged on nights and weekends, or dismissed as a luxury.

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For Phelps, who lived one of the more regimented existences during the past two decades, golf represents an opportunity to compete in venues that have a little more variety than 50-meter pools all set to the same temperature.

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She toggled between two existences.

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