摘要 : This paper mainly centers on the development of American English vocabulary and its causes .To English learners, it will be helpful for them to get to know clearly the outline of American English vocabulary and find answers to man... 展开 This paper mainly centers on the development of American English vocabulary and its causes .To English learners, it will be helpful for them to get to know clearly the outline of American English vocabulary and find answers to many puzzling phenomena, such as why the American English vocabulary is so numerous and jumbled; why there are so many foreign words; why the synonyms are so plentiful and why the spellings of American English are so disorderly, etc. Meanwhile, through vocabulary study, English learners can know well American history, politics, economy, culture, social problem, science and technology and so on. 收起