Here's why:
* Every dialect has its own grammar: All languages, including dialects, have a systematic structure and rules for how words are formed and sentences are constructed. This is their grammar.
* Standard English is just one dialect: It gained prominence due to social and political factors, but it's not inherently superior or "correct."
* No dialect is inherently "right" or "wrong": Each dialect is equally valid and serves as a means of communication within its community.
It's important to understand that:
* Prescriptive grammar focuses on rules and standards considered "correct," often based on a particular dialect (like Standard English).
* Descriptive grammar simply describes how language is actually used by speakers, acknowledging the variations within dialects.
While there are differences between dialects, these differences shouldn't be seen as grammatical errors. They are simply variations in pronunciation, vocabulary, and grammar that reflect the unique history and cultural context of a particular group of speakers.