Abstract
Understanding is discussed through the questions of differential and integral used in thermodynamics, and so on. The aim of the discussion is engineering education for students whose major is mechanical engineering. The understanding discussed here is the ability to understand textbooks of specialized field and graduate thesis. Questions about basic of differential and integral give discussions about shortage of study, shortage of review and so on. Question about calculation of mean specific heat shows the importance about recognition that each subject has different way of thinking. In addition, the question give the discussion about the way of calculate mean specific heat should be understand by students. Discussion about task of heat transfer suggests how to read textbooks.