‘Lǜ shī’ (regulated verse) is a highly structured classical Chinese poetic form that originated in the Tang dynasty. It consists of exactly eight lines, each with either five or seven characters, and follows strict rules for tone patterns, parallelism in the middle two couplets, rhyme (usually on level-tone words), and tonal symmetry. The character 律 (lǜ) means 'rule', 'regulation', or 'law', reflecting the poem’s rigid formal constraints; 诗 (shī) simply means 'poem' or 'verse'. Together, they denote poetry governed by precise metrical and rhetorical conventions.

This form was mastered by great poets like Du Fu and Li Bai and remains central to understanding classical Chinese literature and aesthetics. While rarely composed today outside scholarly or artistic contexts, lǜ shī is studied extensively in Chinese language and literature courses, and its influence persists in modern poetic sensibilities. Recognizing its structure helps learners appreciate how sound, meaning, and syntax intertwine in traditional Chinese poetry.