To study tree rings, researchers generally take a pencil-sized core from a tree.

为了对年轮进行研究，研究人员通常会从树木取出一块铅笔大小的核心部分。

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To study tree rings, researchers generally take a pencil-sized core from a tree.

为了对年轮进行研究，研究人员通常会从树木取出一块铅笔大小的核心部分。

youdao