The paper aims to propose the integrated approach on concept diagnosis for English grammar to ESL students in a Taiwanese classroom. The basic
unified English grammar exam with ten questions was used to investigate the performances among thirty-seven daytime freshman students, and thirty-seven extension students. Method of Interpretive Structural Model (ISM) is used to explore the test item hierarchies while Grey Structure Modeling (GSM) is used to cluster the examinees into different groups.
Besides, the method of Grey Student-Problem chart (GSP) is applied to investigate the different performances of daytime and extension students.
Through the integrated methods of ISM and GSM, it is clear to provide the concept structures for each group, and the information of concept diagnosis is also provided. The results not only benefit for teachers to
provide adaptive teaching methods and remedial instructions, but also provide clear graphs to the parents to understand their children’s learning styles, strengths and weaknesses. Besides, by implementing ISM and GSM, both teachers and students can enjoy learning English grammar under a very happy atmosphere, and this could be defined as the “Impression Kansei Information”.