走廊空无一人，但一盏闪烁的灯发现了他们，触发了无声警报器。

The corridor was empty, but they could see by a blinking light that a silent alarm had been tripped.

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现在我们靠无声警报器和暗藏照相机。当然了，还有就是每个柜里的一些钱作了记号。

Now we rely on silent alarms and the hidden cameras, and, of course, some of money in each cage is marked.

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