Regulated verse – also known as Jintishi (traditional Chinese: 近體詩; simplified Chinese: 近体诗; pinyin: jìntǐshī; Wade–Giles: chin-t'i shih; lit. 'modern-form poetry') – is a development within Classical Chinese poetry of the shi main formal type. Regulated verse is one of the most important of all Classical Chinese poetry types. Although often regarded as a Tang dynasty innovation, the origin of regulated verse within the Classical Chinese poetic tradition is associated with Shen Yue (441–513), based on his "four tones and eight defects" (四聲八病) theory regarding tonality.[1] There are three types of regulated verse: the eight-lined lüshi, the four-lined jueju, and the linked couplets of indeterminate length pailu. All regulated verse forms are rhymed on the even lines, with one rhyme being used throughout the poem. Also, and definitionally, the tonal profile of the poem is controlled (that is, "regulated"). Furthermore, semantic and tonal parallelism is generally required of certain interior couplets. During the Tang dynasty, the "Shen-Song" team of Shen Quanqi and Song Zhiwen greatly contributed to the development of this Classical Chinese verse form.