(Where+do+language+biases+arise+from+and+what+can+be+done+to+prevent+my+own+language+biases+from+hampering+the+teaching+of+my+future+students?)

I think the largest part of it is to realize like the book strives to tell us that there is no one correct way to use language. The way to focus on teaching English is to teach the correct ways to use different types of English so that the student may flourish. Another word for this is code switching. The student should be able to know how to talk to students and peers his own age as well as change the way he speaks to his teacher or principal. The student could potentially want or have a part time job so he needs to know the etiquette of interviews and the proper way to communicate with customers as well. If a student is deficient in any of these manners it is not the teacher's job to roll their eyes or be judgmental about where the student is at level wise. It is the job of the teacher to assess what lessons the student needs and to adjust the curriculum as such that any knowledge gaps they may have are addressed.