It should be a signal that the world has surged ahead and they've been left behind in its wake.

这应该是一个警示信号：这个世界正在有如巨浪般向前涌动，而他们已经落后于时代了。

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Ambulances will digitally broadcast their out-of-my-way signal into cars ahead or even require them to automatically slow down and pull over.

救护车将其数字信号广播到前方的汽车网络中，甚至可以使它们自动减速并靠边。

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Finally, once a police car has the Tahoe in view and the road ahead is clear, a second signal slows the engine down.

最后，只要它进入警车的视线内，并且前方道路通畅，第二个信号就会让它的引擎慢下来。

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In most places in the world, a green light is a signal to move ahead.

VOA: special.2010.05.23

Retail experts warned the latest figures sent out a "worrying signal" ahead of the crucial Christmas sales period.

BBC: Shopper

Instead, they look more broadly at financial imbalances, particularly excessive growth in credit, which tends to signal problems ahead.

ECONOMIST: Yesterday's financial architecture needs refurbishing

It may also signal further cuts ahead, particularly in Europe, as inflationary pressures subside and the need to spur growth takes priority.

FORBES: Central Bank Rate Cuts: Just The Beginning