According to If Black English Isn't a Language Then Tell Me What Is how have Black English and American English influenced one another?

Black English and American English have influenced each other through mutual borrowing of vocabulary, syntax, and other linguistic features. The book argues that Black English has had a significant impact on American English, enriching its vocabulary and contributing to the development of new slang and expressions. Similarly, American English has influenced Black English through historical contact and social interactions within the United States.