The conflict degenerating into civil war is everybody's nightmare scenario.

这场冲突恶化成内战成为每个人的恶梦。

《柯林斯英汉双解大词典》

But the war years were more like a nightmare, and my memory is full of holes.

但战时的岁月就不啻是一段噩梦，而我的回忆充满了缺口。

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But then, on the third day of the Six Day War, their long nightmare ended.

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It is considered by many to be the quintessential film about the nightmare of the Vietnam war.

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