Cycling in the fast traffic lane is really dangerous.

在快车道上骑自行车， 可真悬。

《新英汉大辞典》

She thought it was safer to stay with the slow traffic; but then she heard a voice (" not out loud, but in my mind ") telling her to get in the fast lane.

她本来认为随着缓慢的车流一起慢慢前行会比较安全，但她那时突然听到了一个声音(“不大，但却清楚地进入头脑中”)告诉她驶入快车道。

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Many areas require that slow drivers drive in the far-right lane. Faster moving traffic operates in the middle lanes. The fastest cars drive on the far-left side — also called the fast lane.

许多地区要求开得慢的司机在最右侧车道行驶，更快的车流在中间车道行驶，开得最快的司机在最左边车道也就是快车道行驶。

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