A quatrain is a type of stanza, or a complete poem, consisting of four lines.

Classical Chinese poetry forms are poetry forms or modes which typify the traditional Chinese poems written in Literary Chinese or Classical Chinese. Classical Chinese poetry has various characteristic forms, some attested to as early as the publication of the Classic of Poetry, dating from a traditionally, and roughly, estimated time of around 10th–7th century BCE. The term "forms" refers to various formal and technical aspects applied to poems: this includes such poetic characteristics as meter, rhythm, and other considerations such as vocabulary and style. These forms and modes are generally, but not invariably, independent of the Classical Chinese poetry genres. Many or most of these were developed by the time of the Tang Dynasty, and the use and development of Classical Chinese poetry and genres actively continued up until the May Fourth Movement, and still continues even today in the 21st century.