air horn

基本解释

We use this air horn to give a signal in the event of emergency.
应急情况下，用这个气喇叭发信号。
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The fighting starts when a signal such as an air horn or whistle blows, and can last anywhere from a few minutes to a few hours.
当用号角或口哨发出信号时，大战就可以开始了，在任何位置都行，能持续几分钟到几个小时。
Second most harmful to our ears was the air horn, which exposes our ears to damage inducing levels of 123.6 decibels. This was followed by the drum, which reached 122 decibels.
对我们的耳朵造成伤害排名第二的就是气喇叭，它能发出123.6分贝的声音，紧跟其后的就是桑巴鼓，达到122分贝。

The horn obviously is a brass instrument and what makes the sound is a vibrating column of air.
显而易见的,圆号是个铜管乐器,它通过震动空气柱来发出声音
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Or how the horn honks automatically when filling the tires to tell when the air pressure is right.
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But once or twice in every song, he would put his horn to his lips, stand ramrod straight, and play sweet, fast notes that danced in the air.
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