The sun sets down slowly along the endless undulating mountains. The surging Yellow River running past the tower flows seaward.

落日向着一望无际、连绵起伏的群山冉冉落下，流经楼下的黄河奔腾咆哮、滚滚流归大海。

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Everyone knows that the sun rises in the east and sets down in the west.

人人皆知太阳从东方升起，从西方落下。

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The teacher told us that the sun rises in the east and sets down in the west.

老师告诉我们说，太阳从东方升起，从西方落下。

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Generally, right after the sun sets we sort of lay our heads down on the pillow.

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Bring earplugs (it can be noisy sleeping amongst all the other trekkers) and a down sleeping bag and jacket as temperatures plummet once the sun sets.

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