horn loudspeaker

例句：

1. 1. The horn loudspeaker was used to alert the crowd of an approaching storm.
   喇叭被用来警告人群一场即将到来的暴风雨。
2. 2.The loudspeaker system is responsible for broadcasting announcements throughout the campus.
   扩音系统负责在整个校园内广播公告。
3. 3.The loudspeaker was so loud that it drowned out all other sounds in the room.
   扩音器的声音太大了，以至于房间里的其他声音都被淹没了。