The car bumped on the uneven surface of the gravel road.

汽车在高低不平的砾石路面上颠簸着。

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Hirvonen and Loeb both slowed dramatically on the first day's final stage in order to avoid being the first cars on the road on Saturday, when they anticipated loose gravel on the surface would slow the leader relative to the chasing pack.

CNN: Latvala victory ends Loeb's winning streak