Purpose: The integration of visual and verbal modes in educational materials, particularly in school textbooks, plays a chief role in enhancing the learning experience. Thus, the present study aimed to analyze the intersemiotic complementarity of verbal and visual modes in three English school textbooks from two countries with different policies toward English education at public schools, Iran and Malaysia. Methodology: Employing a qualitative descriptive approach, this study analyzes the intersemiotic complementarity within English school textbooks used in the first grade of high school in Iran and Malaysia, focusing on three selected textbooks: Prospect 1 (Iran), Form 1 (Malaysia), and Pulse 2 (Malaysia). The analysis was guided by Royce's (1998) framework for intersemiotic complementarity, with a particular emphasis on the ideational metafunction. This involved examining the coherence between visual representations (images) and textual content (dialogues) to assess how these elements complement each other in conveying educational content and facilitating learning. Findings: The analysis revealed a marked disparity in the integration of visual and verbal modes between the textbooks from the two countries. Iranian textbooks, specifically Prospect 1, demonstrated a significant disconnect between images and text, often leading to confusion and potentially hindering students' learning. In contrast, the Malaysian textbooks (Form 1 and Pulse 2) exhibited a high level of intersemiotic complementarity, with images effectively supporting and enhancing the textual content, thereby facilitating a more cohesive and comprehensible learning experience for students. Conclusion: The study demonstrates the importance of cohesive integration of visual and verbal elements in textbooks to support effective learning, highlighting the need for strategic multimodal design in educational materials. By ensuring a cohesive integration of visual and verbal elements, textbooks can become more effective tools in enhancing comprehension and improving learning outcomes. This research contributes to the growing discourse on multimodal education, suggesting pathways for future investigations into the optimization of textbook design for enhanced educational impact.
