Do you have to write seven sentences in vernacular poetry?

It doesn't have to be seven sentences to write vernacular poetry, and modern poetry has never stipulated a few words. Modern poetry, also called "vernacular poetry", is a kind of poetry. Compared with classical poetry, it is generally informal in format and rhythm. The discovery of modern poetry can be traced back to the late Qing Dynasty. At that time, under the influence of the May Fourth Movement, some poems imported from the West began to be translated into vernacular Chinese, but the number of these works was not very large, so they were rarely seen.