消防员使用烟雾探测器来发现火灾隐患。

Firefighters use a smoke ___detector to identify fire hazards.

这台金属探测器在机场安检中非常有用。

This metal ___detector is very useful for security checks at the airport.

这个烟雾探测器能准确识别空气中的烟雾颗粒。

The smoke ___detector can accurately identify smoke particles in the air.