A running horse needs no spur.

奔马无需鞭策。

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One cannot shoe a running horse.

正在奔跑的马匹无法钉蹄铁。

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Racegoers will be given a number which will correspond to a horse running in a race.

观看赛马的观众将领到一个与参赛马匹相对应的号码。

《柯林斯英汉双解大词典》

"When you're running against a horse like Orb, you have to be 100 percent fit, " Plesa said.

WSJ: Itsmyluckyday cedes spotlight at Kentucky Derby

It could have been a horse, he thought, but the animal seemed to be running upright, on two feet.

NEWYORKER: Max at Sea

Bothered by the gap in the center of the garland, where it parts on either side, Ms. Blair created a "crown" of roses to top it with one rose for every horse running that day.

WSJ: The Kentucky Derby's Rose Queen