If the radius of the curved terrain is much less than that of the earth, it can be viewed as a combination of a flat-curved-flat terrain.

当曲面地带的半径远小于地球的半径时，这种地带可以被看成平面-曲面-平面地带的组合。

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It is a misconception to think that cross-country skiing is confined purely to flat terrain.

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It could land big rovers or small, on flat terrain or sloped, in all kinds of weather.

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It also makes certain adjustments on its own, such as when a user switches from flat terrain to an incline.

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