They found the least defended area and attacked.

他们找到了防守最薄弱的地区发动了攻击。

《柯林斯英汉双解大词典》

At evaluating the combat effectiveness of the defense system, target's probability to penetrate the defended area is a primary care taking index.

在评估防御体系的作战效能时，目标突防概率是人们关心的主要的性能指标。

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Aerial units or cliffjumping Reapers make the best raiders, as they are unbothered by most terrain, and you can hit your target from its least defended area.

空中单位和能越过悬崖的死神能作出最好的偷袭，因为他们不受大部分地形的干扰，并且你能够在对方防御最薄弱的区域攻击目标。

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Malton, Old Malton and Norton are defended from the river but surface water and backed-up drains have flooded several properties in the area.

BBC: Road to Brawby

For instance, the kiosk explains that Rothermel's deliberate perspective puts the viewer 125 yards from the copse of trees just below Cemetery Ridge in an area of the battle line known as "the Angle, " a jog in the stone wall defended by the Philadelphia Brigade.

WSJ: Capturing Gettysburg | Objects of Valor | State Museum of Pennsylvania | By Mark Yost

As Atletico pressed, Bolton brought back more men and defended deeper, but it was not desperate stuff, and the English side comfortably handled whatever was flung into the area.

BBC: Atletico Madrid 0-0 Bolton