The Readability of English Textbook for the Tenth Grade Students of Vocational High School

This research was aimed to find out whether the English reading texts are appropriate or not in terms of the readability level for the tenth grade students of Vocational High School. This study focuses on the readability level of English reading texts for grade X students of Vocational High School majoring in the
academic year 2018/2019. This study is categorized as descriptive qualitative research. The data of the study was seven reading texts from an English textbook
entitled Bahasa Inggris published by Kementerian Pendidikan dan Kebudayaan in 2014 with various length and genres as the source of data tested. The instruments
of the research were Flesch-Kincaid Grade level. The researcher counts the words, syllables, sentences, the average number of words per sentence and the average
number of syllables per words of the reading text to determine the level of readability of the English texts in students’ textbook. Therefore, the researcher takes a conclusion that this textbook is not appropriate to be used by the students at the tenth grade students of Vocational High School because they can read them
by their own.