Rose and Galen were nearly knocked from the path when a riderless, wild-eyed horse galloped by.

一匹无人驾驭的马儿疯跑过来，差点就把萝丝和加仑撞出小路。

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The best known riderless horse was Black Jack.

VOA: special.2009.05.25

Synchronised fell first time round this year but continued riderless for another five fences before fracturing his leg.

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Most experts agree that an open oval such as the mile-long track at Churchill Downs would present problems for riderless horses.

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