Good morning, boys and girls. There is an indispensable part of American English, which is American Black English. So in our today's lecture,we may focus on some issues about it. It is extremely difficult to say how many people speak Black English because it is not clearly what exactly this would mean. As we know, except for Native Americans, no one is from America. It is estimated that at least 170 ethnic groups live in the United States. American black people make up about 12% of the American population, and about 80% of American black people speak Black English. Because of its lack of formal recognition,American Black English is often treated just as a local slang and linguistic deviation. It is only recently that it has become an area of great interest to linguistics, who are keen on learning about universal tendencies in this language and studying language status,attitudes,and the importance of the language. But there are still many controversies about how to describe it and how to explain its origin and development. So we will talk about it in two aspects.