We say an enemy on the move is easy to attack precisely because he is then off guard, that is, unprepared.

我们说运动之敌好打，就是因为敌在不意即无准备中。

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An independent review panel that examined the Libya attack said serious lapses in management and leadership left the consulate badly unprepared, but it also called for a greater commitment from Congress to support the State Department's needs.

WSJ: Senate passes bill to improve embassy security

But women and their doctors commonly don't suspect the disease and are unprepared for an attack.

CNN: Time to read the signs: Symptoms of heart attacks in women