So a natural pearl would have all of those concentric layers of growth from the very inside out.

天然珍珠从里到外都生长着这些同心层。

With each passing year the mollusk's secretions added new concentric layers.

年复一年，软体动物的分泌物增加了新的同心层。

By leaving the pearl buried beneath the giant clam's mantle, he allowed it to grow imperceptibly. With each passing year the mollusk's secretions added new concentric layers.

把这颗珍珠塞在那只车渠的衣膜里面，无形中这珠就可以渐渐大起来了。每年，那软体动物的分泌物都在环绕珍珠周围的薄膜上累积起来。

From the Saddle the Dome rises in a graceful curve a few degrees too steep for unaided climbing, besides being defended by overleaning ends of the concentric dome layers of the granite.

从鞍座开始，圆顶以优美的曲线升起，对于独立攀登来说太陡了几度，此外还受到花岗岩同心圆顶层过度倾斜的端部的保护。