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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It can be very small, small enough to fit in your pocket, or large, but not as large as a car. it is used to make noise. it can be used to give a signal.

它可能是非常小的，够小的在你口袋中适合，或大的，但是不如大的当车。它用来制造噪音。它可能用来给信号。

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Then, the cutters give a signal and the men all simultaneously fall back. The flock rushes in, covering the body completely, their heads disappearing as they bend down to tear away bits of flesh.

后来，那位切割者发出了一个信号，所有的男人同时后退，成群的鸟急冲直下，立即覆盖了尸体，它们的头部在弯上去撕扯肉片时看不到了。

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There are molecules in cells that give the DNA the signal that it's time to transcribe and express a gene, those are called transcription factors, we'll talk about them a bit later.

在细胞中有些分子能够,给DNA发出信号告诉它,是时候转录和表达某基因了,这些分子叫做转录因子,晚些时候我们会讲它们

耶鲁公开课 - 生物医学工程探索课程节选

Simply because of the format of this radio station we have to give a signal to our stations.

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In an interview in August Maude outlined one example where he said a permanent secretary's behaviour was "designed to give a signal to all the officials in the room that they needn't bother about what Francis Maude wanted".

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"The decision seems to be designed to set a precedent and give a strong signal to the armed forces that the days of meddling in politics are over, " wrote Suat Kiniklioglu, a senior member of Turkey's ruling Justice and Development Party, in an e-mail to CNN.

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