People sat impatient and frightened in the dark as if an unseen enemy had landed from Mars.

人们焦急不安、惊惶失措地坐在黑暗中，好像有一名来自火星的看不见的敌人已登上了地球。

youdao

As I lay in bed, I thought of the chemicals, the unseen enemy, filling my room.

当我躺在床上，我就想着看不见的化学敌人正在充满我的房间。

youdao

The opening scene of SEIKAI NO MONSHOU is a chaotic space battle involving humanoid combatants in a huge capital ship against an unseen enemy.

那个打开 SEIKAI 的现场没有 MONSHOU 是一场混乱的空间战争包括对抗一个未见过的敌人一个极大的主力舰的像人争斗者。

youdao

Now they're facing this unseen enemy in the form of mobile phone masts.

BBC: NEWS | UK | Phone masts 'confusing' pigeons