这个平行线是一个有半径的圆，这个半径是小于a的，因为如果这个环越靠近北极点，它的半径实际上会越来越小。

So now, this parallel as a circle of radius, well, the radius is less than a because if your vertical is to the North Pole, it will be actually much smaller.

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构成建物的长容积桶状圆拱平行于树列及等高线，且接连了外部空间的地层构造。

The long dimension of the barrel vaults that form the building is parallel to the allees and contours, continuing the layered structure of the outdoor space.

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地球是圆的，而我们却偏偏走在两条不能相交也不能跨越的平行线上。

The Earth is round, but we walk actually on the parallel line which two cannot intersect cannot surmount.

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