Lily Wong Fillmore argued that native English speaking teachers take Language for granted. Those who know English well, may not understand that students “who are speakers of varieties of English––[may] find the academic registers used in texts to be more difficult to untangle than do speakers of “standard English” who have only the spoken register”.
Reference:
Fillmore, L., & FIllmore, C. (n.d.). ICSI Berkeley. WHAT DOES TEXT COMPLEXITY MEAN FOR ENGLISH LEARNERS AND LANGUAGE MINORITY STUDENTS?. Retrieved April 28, 2018, from http://www.icsi.berkeley.edu/pubs/ai/textcomplexity13.pdf