In spite of that, recent studies are not very encouraging in the field of this specific language variety for its special combination with the black music culture.  Most sociologists, linguists and psychologist believe that Rap becomes a means of self-differentiation that helps forge group identity, solidarity and ethnic pride, and the language used in Rap is often a kind of passive resistance to oppression, discrimination or cultural aggression. Likewise, it’s a fact that Black English has become an important constituent of American English with the flourish of Rap music.
The last but not the least important reason for taking up the present study is the great influence of Black English on American English as a result of the rapid development of popular culture. In addition, with the Rap music’s entry into China, the zeal for the western popular culture is higher than ever before. That would not only benefit Chinese people’s English learning a lot, but also push the development of Chinese Rap music into a new stage.

II. Researches on Black English and Rap music

2.1 Researches on Black English at Home and Abroad
    Black English is the term used for English variants spoken by some African-Americans, and some studies show that some none-African-Americans even speak it. Edwards W.F. pointed out, “It has gone through decades before getting the term of “African-American vernacular English”, which sometimes is shortened as AAE in his Sociolinguistic Behavior in a Detroit Inner-city Black Neighborhood (Edeards 93-115) . Before Black English, a number of names have been used, such as Ebonics and Black Vernacular English. During the mid and late 1960s, the name Negro-None-Standard English was often used in Zhao Shuguang’s research during the writing Prelimilary Exploration of the Impact on the Development of South and North America’s Music from Black English (Zhao 4-5). It is obvious that the terms for this language variety change more or less in step with terms of self-identification that speak for it.
Sociologists, linguists and psychologists generally believe that it is common for oppressed people (like African slaves in the Americans) to choose a different dialect from their oppressors. This is done to subtly rebel against the oppressor and his culture, and to differentiate themselves, as well as to cultivate pride among their community. Zhang Ming laid out his view above in the article The coming into being and features of Black English (Zhang 9-10) .
Like other studies, the main purpose of studying Black English is better to serve the society. Those are the favorite subjects for western linguistics, whereas studies on Black English in China are not as heated as that of America.
Studies on relationship between society and language in China maybe traced back to the beginning of civilization. However, the notion of sociolinguistics has been introduced in China in 1980s with the introduction of the foreign monographs. From then on, a discipline called sociolinguistics has been set up in China. But studies of Black English are really scant compared with that of America, because the main purpose of the study is to benefit society. There are more general introductions of sociolinguistics than detailed descriptions of Black English, which is certainly determined by the situations of China. There are still some papers or chapters in books introducing what Black English is and what features it possesses, though they come out much later and have no breakthrough in researching, just representing what have already been found in USA.
2.2 Researches on Rap music at Home and Abroad
The Oxford English Dictionary defines “Rap” as “a style of popular music (developed by New York Blacks in the 1970s) in which words (usually improvised) are spoken rhythmically and often in rhyming sentences over an instrumental backing”. Its original meaning is to identify and signify a particular sound that is made when one solid object is struck against another and the sound of a Rap is sometimes used as a means of signaling anything heavier than what would be an ordinary blow. As Chen Daoming put, “Rap itself is a musical genre, which combines unsung rhythmical rhyming texts with beats, which are in fact the same that funk music uses”, in The Feelings towards Colored Skin─Culture of Black Americans’ Music (Chen 47-80) . 美国黑人说唱乐的语言特色及其社会影响(2):http://www.751com.cn/yingyu/lunwen_8154.html