報警器的用法和樣例：
例句
-
雖然家中剩下的貴重物品現都存放在銀行里了，他還是安裝了999電子報警器。
Although the family's remaining valuables are now lodged with the bank, he has installed an electronic999 dialling system. -
火警報警器響個不停。
The fire-alarm kept jangling (away). -
報警器正發出火警警報。
The fire-alarm is giving warning of fire.
