The captain explained that he used a tool with a sharp point to make dots and small dashes in thick paper.

上尉解释说，他使用一种锋利带尖的工具在厚纸上打出圆孔和小的凹痕。

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The captain explained that he used a tool with a sharp point to make dots and small dashes in thick paper.

上尉解释说，他使用一种锋利带尖的工具在厚纸上打出圆孔和小的凹痕。

youdao