Regulated verse, also called Jintishi (traditional Chinese: 近體詩; simplified Chinese: 近体诗; pinyin: jìntǐshī; Wade–Giles: chin-t'i shih; meaning "modern-form poetry"), is a type of Classical Chinese poetry. It is one of the most important forms in Classical Chinese poetry. Although often linked to the Tang dynasty, its origins are connected to Shen Yue (441–513), who developed a theory called "four tones and eight defects" about sound patterns in poetry.

There are three types of regulated verse: the eight-lined lüshi, the four-lined jueju, and the linked couplets of any length called pailu. All regulated verse poems rhyme on the even-numbered lines, using the same rhyme throughout the poem. The sound patterns in the poem are controlled, meaning they follow specific rules. In addition, certain lines inside the poem must match in both meaning and sound.

During the Tang dynasty, two poets named Shen Quanqi and Song Zhiwen helped develop this form of Classical Chinese poetry.

Formal rules

Regulated verse includes three types of poetry called lushi, jueju, and pailu. These forms differ from older styles of poetry, called gushi, because they follow specific rules. These rules include:

• Each type of poem has a set number of lines. Jueju poems have four lines, lushi poems have eight lines, and pailu poems have an even number of lines with no fixed limit. In all cases, lines are grouped into pairs called couplets.
• All lines in a poem have the same length, measured by the number of characters or syllables. Most poems use lines with five or seven characters, though some use six characters. The line length also helps classify the three main types of regulated verse into smaller groups.
• Rhyming is required in all poems. Rhyme follows a specific pattern based on ancient rules. Rhymes are often determined using official lists of sounds from the past, not modern speech. Level tones (smooth sounds) rhyme only with other level tones, and non-level tones (more varied sounds) rhyme only with other non-level tones. The first line of a poem often sets the rhyme, especially in seven-character poems.
• The pattern of tones (level or non-level) in each line follows fixed rules. In Middle Chinese, four tones were used, with level tones (similar to modern first and second tones in Mandarin) being the most important. Regulated verse requires alternating patterns of level and non-level tones.
• Parallelism is required, meaning that words in paired lines must match in meaning, grammar, or sound. For example, colors, actions, or numbers might be repeated. In lushi poems, the middle two couplets have internal parallelism, where the third and fourth lines match, and the fifth and sixth lines match. Jueju poems may have some parallelism but are less strict. Pailu poems require parallelism in all couplets except the first and last.
• A pause, called a caesura, is placed in each line. The main rule is that the pause occurs before the last three characters in a line. For example, in a six-character line, the pause divides the line into two equal parts. In a seven-character line, a smaller pause usually appears between the first and second pairs of characters.