Electronic mail a method of sending data from one place to another anywhere in the world using telephone wires radio waves optical fibre cable or satellite.

电子邮件把数据从一地点经电话线、无线电波、光学纤维或卫星送往地球上任何地点的方法。

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For example, a telephone call may travel by means of copper wire, fiber-optic cable, and radio waves as the call is sent from sender to receiver.

例如，电话中的通话从讲话人传送到听话人，其间可能要通过铜线、光缆和无线电波进行传输。

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The new law will widen the agency's monitoring to include all crossborder cable traffic (from the current limitations on the FRA to monitor only military radio communications).

ECONOMIST: A new surveillance law causes a rumpus in Sweden

And while -- while you might not always know it from watching the cable news shows, or listening to folks on the radio, I think it's clear that we stand at one of those moments.

WHITEHOUSE: President Obama at Points of Light Forum in Texas