Since commutes tend to be heavier in one direction than another, most fleet vehicles would incur extra costs dead-heading to return to the concentration of commuters for a second and third round during the rush periods.

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On a fog-shrouded evening on the penultimate day of 1906, a dead-heading train roared down this stretch of tracks near Washington's Catholic University, coming upon a slower passenger train heading the same direction on the same track.

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One of the early indications that the one-way street is heading for a dead end is the ratio of declarative statements to questions.

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The project took time to come together and it was only after much searching and heading down a few dead ends that Marwah found Mona, as many of those she approached did not want to talk about their illness as it may jeopardise their position in society.

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