Try your double low-tone whistle with the same temporal spacing and the same notes, and you will see the text "two low" printed to the screen. If you want to see the functioning of the cmdWhistle.pl

尝试以同样的时间间隔并以相同的音调吹两声低音调口哨，您将看到文本 “two low” 打印到屏幕上。

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He spoke in a confidential tone, his voice low.

他低声用隐密的语气说话。

《牛津词典》

The Rabbit said in a low, hurried tone.

兔子急忙低声说。

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Additionally, the TV's picture engine employs multi-frame analysis to help create missing resolution, and Sony's Super Bit Mapping technology incorporates 14 bit up-scaling, processing and pixel mapping to smooth gradation and improve the quality of low-tone pictures.

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Sonia maintains a low-key tone when detailing her ambitions.

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The tone of the event was much more low-key than we expected, with an audience that was much harder to please than the GDC crowd.

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