to sound an air attack

• 发出防空警报

to sound an air attack的用法和样例：

例句

1. Here in Haifa, air sirens continue to sound.
   防空警报仍未在海法撤销。
2. Humans and Zentraedi looked to the Sentinels suspiciously.
   防空警报呼啸着，人类和天顶星人可疑地看着哨兵。