警笛的哀嚎划破了夜空。

The wail of a police ___siren cut through the night air.

当测试警报响起时，请冷静地前往避难所。

When the test ___siren sounds, please proceed calmly to the shelter.

在那本反乌托邦小说中，城市警报器不停的鸣响是对持续监视的冷酷提醒。

In the dystopian novel, the constant blare of the city ___siren was a grim reminder of the ongoing surveillance.