这种类型的搬运称为河底滚沙。

This type of transport is called saltation.

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“你应该也来打个滚儿，沙斯塔，”它喷着鼻息，“这是最最振作精神的了。”

"You ought to have one too, Shasta," he snorted. "It's most refreshing."

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沙斯塔吃完了他的早餐（这是他所吃过的早餐中最最精美的一餐），布里说道，“在重新装上马鞍子以前，我想我要美美地打个滚。”

When Shasta had finished his breakfast (which was by far the nicest he had ever eaten), Bree said, "I think I'll have a nice roll before we put on that saddle again."

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However dimly that light came through to you, suffering so acutely from the rough denial of the very existence of American ideals, part of it must have come through American delineation of American characters.

不管遇到何种艰险，哪怕翻山越岭,哪怕趟水滚沙，这些都需要,生动的角色来表现出来。

耶鲁公开课 - 1945年后的美国小说课程节选