Knock on wood, that has resulted in quite a few no-changes in the last several years.

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Incontinence is a health issue that has, knock on wood, not yet hit my radar screen.

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"So far, knock on wood, we've dodged on this one, " said D.

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For most Americans life is actually long (knock on wood).

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Meanwhile, toy giant Mattel was showing off its Angry Birds Knock On Wood game, which I first spotted last month at the Consumer Electronics Show in Las Vegas.

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