The wheels of language run so smoothly that one rarely bothers to stop and think about all the resourcefulness and expertise that must have gone into making it tick.

语言的齿轮运作得如此顺畅，以至于人们几乎从未想过要停下来思考那些能使语言变得更加优美的智慧和专业知识。

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In fact, all the other cars in this segment send engine power to the rear wheels if not all four wheels, like the Audi A6.

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Offroad ("propshaft by wire"): All four wheels are also driven whenever offroad mode is intentionally activated.

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Each prototype has six-wheel steering, which means that they can turn all six wheels and crab sideways.

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