Abstract: Based on systemic functional linguistics,the present study analyzes what influence the grammatically cohesive resources of reference have on readability,and probes into variation of the readability of an excerpt from the novel Alice's Adventures in Wonderland and its eight adapted versions.As an extension of Lassen's and Huang and Liu's readability researches in light of Halliday's notion of grammatical complexity,this study proposes several indexes of readability related to certain dimensions of reference.In line with each index,readability of the original and adapted versions has been figured out.From the analysis no uniform readability rankings have been founded.This study serves as an approach to readability from the grammatical end of lexicogrammar to meaning.