Two blind subjects used clicks and their echoes to distinguish objects like a car, tree or flag pole.

两名盲人受试者通过敲击和听其回声来辨别诸如汽车、树或棋杆等物件。

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A black flag in a car race is the signal for a driver to go to the pits.

在汽车比赛中，黑旗是要车手进维修站的信号。

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Soaking wet, she decided to flag down the next car.

她浑身湿透，准备招手拦下一辆车。

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No driver is allowed to pass another car while the caution flag is posted, so at that point, to win, all Kanaan needed to do was finish without crashing.

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Every car was waving a flag.

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Hildebrand was driving to certain victory, he spun his car in the marbles on the very last turn of the last lap, giving Wheldon in the Reagan car the lead and the checkered flag.

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