A regular group of lines in poetry constitutes

A regular group of lines in poetry is called a stanza. It is a unit of poetic lines that are usually separated by a space and are characterized by a fixed number of lines, a particular rhyme scheme, and a specific metrical pattern. Stanzas are used to organize a poem and to convey different thoughts, ideas or emotions in each unit, allowing for breaks or shifts in the poem's tone, mood, or theme. In contrast, rhythm refers to the pattern of sounds and syllables within a line or verse, while metre is the regular pattern of stressed and unstressed syllables in poetry.