科学家根据动物的特征进行系统的分类。

Scientists perform systematic ___classification of animals based on their characteristics.

图书馆里的每本书都有一个特定的分类编号。

Every book in the library has a specific ___classification number.

科学家们正在讨论如何对这个新发现的昆虫进行分类。

Scientists are discussing the ___classification of this newly discovered insect.

军方在机密报告中对该文件进行了最高级别的保密分类。

The military gave the document the highest level of security ___classification in the confidential report.