William Carlos Williams is one of the most influential poets in American literature. He rejects the traditional poetic forms and prosody. Thus, he adopts a defensive strategy against the artificial European models. Williams has established new poetic forms and prosody, such as stanza arrangement, repeating some phrases, the use of caesura, internal rhyme and rhythm. Therefore, Williams' poetic forms and prosody are natural and organic. They are derived from the music, spontaneity and order of the American language and speech. The most rhetorical feature that revolutionizes Williams' poetry is “variable foot" that brings harmony and flexibility to Williams' poetry. It can be argued that the correspondence of Williams' poetic forms and themes sincerely depicts the tangible and intangible elements of American environment and society.