定义a literary movement launched by British and American poets early in the 20th century that advocated the use of free verse,common speech patterns,and clear concrete images as a reaction to victorian sentimentalism.
代表作家及作品ezra pound:in a station of the metro,hilda doolittle:oread,william carlos williams:the red wheelbarrow
原则：1.content should be presented directly,through specific images where possible.
2.every word should be functional,with nothing included that was not essential to the effect intended.
3.Rhythm should be composed by the musical phrase rather than the metronome.