属于 (shǔ yú) is a two-character verb meaning 'to belong to' — expressing ownership, membership, classification, or affiliation. The first character 属 (shǔ) originally means 'to be affiliated with' or 'to be under the jurisdiction of', while 于 (yú) is a classical preposition indicating direction or relation; together, they form a fixed compound used exclusively in this sense. Unlike English 'belong to', 属于 is not used with continuous or progressive aspects and never takes aspectual particles like 了 or 过.

This verb is commonly used in formal, academic, or administrative contexts — for instance, when stating nationality, organizational membership, tax categories, biological taxonomy, or property rights. It typically follows the subject and precedes the noun phrase indicating the group, category, or owner (e.g., 'this book belongs to me' → 这本书属于我). It does not function as a standalone noun or adjective and cannot be reduplicated or modified by degree adverbs like 很.