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。

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Air is forced up from the buoy counterweight tube during downward motion causing the balls to seal the air ports in the valve, thus forcing the air to flow into the whistle.

空气在向下运动过程中受到浮标向上的推力，使阀球将阀门里的气舱密封住，这样迫使气流进入雾笛。

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If it fails to inflate, or you need top up the air, blow into this tube. A light and whistle are provided to attract attention.

如果充气失败，或者你需要补充充气，向管子直接吹气即可。一个照明灯和哨子供你引起注意使用。

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Suddenly the air was cut by a sharp whistle not far away.

VOA: special.2010.04.03

He loaded the volumes onto a little cart and as he ran he heard the bullets whistle through the air above him.

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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.

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News of Mr Chavez's resignation caused hundreds of flag-waving and whistle-blowing Venezuelans to surround the city's air force base, La Carlota, in the hope of seeing Mr Chavez' departure from the country.

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