In recent years, to activate the classes by using the electronic information technology has been noted. The purpose of this study note, is to propose a new function to the digital textbooks of language arts. Functions proposed in this paper, while having the potential to greatly improve the language lessons, have not been tried so far. To develop a method of use of information transmission technology in the classroom, Ministry of Education, Culture, Sports, Science and Technology is doing the experiment in 20 schools from 2013. Some of the results are published in the HP, what is reported as an example of the language arts is a task underline textbooks. But it can work even on paper. Capitalize way the characteristics of digital textbooks of language arts, is a work of sorting and excerpt the text freely. This has the effect in two ways: one is to make possible to reread a text from a new perspective, and the other is promoting intensive reading. In this paper, I presented the case of "KOKORO" as an example of using this function.