The purpose of this study is to elucidate the pedagogical functions of the provided visual images in the English textbooks, explore the visual images exploited for learning tasks, and to seek whether visual images and the content reinforce each other as depicted in textbooks of Senior High School.  Visual image representations are frequently employed in literature for teaching English as a foreign language and in teaching and learning materials. Visual resources can be described as tools that teachers and students can use to enhance language learning in the classroom.

This research adopts the Visual Grammar Theory by Kress and Leeuwen (2006) to elucidate the pedagogical functions of provided visual images in the textbook from a multimodal analysis. Visual data were collected from the chosen English textbooks for Grade X and XI. This study also uncovered students' and English teachers' statements about the functions of the visual images in the textbooks to strengthen the critical analysis of the images represented in the English textbook.

The results showed that visual images help the teachers in teaching material and as a tool to assess students understanding in material. The textbook makes full use of visual images for pedagogical learning since many visual images in language textbooks serve informational or illustrative purposes rather than being only decorative. In terms of the exploitation, visual images serve additional information, illustration text and makes language task more interesting. Concerning the suitability of the visual message and the written message to explain the content, several images of the message do not match the written text. These findings imply visual images can be used as a source of teaching materials by teachers in the classroom. The teachers should be more considerate in choosing the images in the textbook that will be used as a tool to help them. Teachers must understand how visual materials function as pedagogical resources to aid them in their lesson plans.