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"Mother tongue" is the essay written by Amy Tan where she shows the problems that her mother, a Chinese woman, suffered from not speaking English in a standard way, spoken by an American and how she was impacted by it. In most of the text, Tan organizes information using a structure called comparison and contrast, where it presents the similarities and differences between standard English and English considered "broken" and how people who use these two types of English are treated and impacted.