If the player fails a concussion test, he or she must follow a staggered series of follow-up tests often over several days before being cleared to return to activity.

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Every day, though, presented a series of political tests that he either had to pass or find a way to avoid.

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Every day is like a series of multiple-choice tests: Go to the gym or keep working?

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But the rescue of Fannie and Freddie and the travails at Lehman are merely the latest in a long series of tests that the authorities will have to face over the next year or so.

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Once matched with a living donor, a patient contacts his or her hospital, and the transplant occurs once the donor has been medically cleared by a series of tests.

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