He was interned as an enemy alien at the outbreak of the Second World War.

他在第二次世界大战爆发时被作为敌国侨民扣押了。

《柯林斯英汉双解大词典》

So, before you defeat an enemy alien before you come to overcome the internal enemy.

所以，在你战胜外来的敌人之前，先得战胜你内在的敌人。

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However, the comic version of Raza is not an enemy of Iron Man, but an alien cyborg who is a member of the space pirate gang known as the Starjammers.

然而，漫画里的拉扎并不是铁人的敌人，而是一个外星电子人，他是一个名为“星际干扰机”的太空海盗团伙的成员。

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"XCOM: Enemy Unknown" is a science fiction, strategy game pitting Earth against an invading alien force.

CNN: Two games in one in 'XCOM: Enemy Unknown'

An alien bug that causes diarrhoea, for instance, is as much an enemy of the microbiome as of the host.

ECONOMIST: Modern medicine