响亮的喇叭声是国王驾到的信号。

A fanfare signalled the entrance of the king.

《牛津词典》

所以汽车有喇叭。这也是为什么有心的司机总是带着信号弹和应急设备。

That's why cars have horns, and why safe drivers carry flares and other emergency gear, and it's why we have safe words and sometimes exacting negotiations.

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由单片计算机控制的计数器自动产生通1秒停4秒的信号，使5路继电器输出带动电喇叭轮流通电。

By single chip computer control of counter automatically generate tong 1 second stop 4 seconds of signal, make no. 5 relay output drive electric horn turns electrify.

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