FIFA regulations state that so long as a player over the age of 21 has not represented their country of birth at any level, then they are free to switch international associations.

国际足联规定超过21岁的球员如果没有代表他出生的国家参加过任何级别的比赛，就可以自由选择为其他国家效力。

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The Dubliner played for England in the 2007 World Cup and under International Cricket Council rules he should be unable to switch allegiance back to the country of his birth until April 2011.

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The 22-year-old Blackburn Rovers full-back has decided to switch allegiance from the Republic of Ireland to the country of his birth.

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London, England (CNN) -- A baby born with a severe birth defect put its parents on opposing sides in a British court Monday over whether to switch off the child's life support.

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