3 sentences

1. 你在测试警报器吗？

   nǐ zài cè​shì jǐng​bào​qì ma?

   Are you testing the alarm?

   Source: OpenSubtitles

2. 防盗警报器突然响了起来。

   fáng​dào jǐng​bào​qì tū​rán xiǎng le qi​lai.

   The burglar alarm suddenly sounded.

   Source: Dong Chinese Dictionary

3. ‎警报器响了吗？

   ‎ jǐng​bào​qì xiǎng le ma?

   Did the alarm go off?

   Source: OpenSubtitles