"Read carefully and think carefully" means reading and thinking. It is about the relationship between reading and thinking, learning and understanding. "Step by step" requires a reasonable reading order, while "close reading" requires understanding on the basis of memory and in-depth understanding of the views of the books read. Zhu said: "Learn from it, and think about it if you are unfamiliar." "The method of reading, read it again, think again; Think it over and read it again. Therefore, readers help him think and often teach his heart to flow on it. If you only read it in your mouth, you don't think about it in your heart and you can't remember it carefully. " It can be seen that "familiar reading" means "making a book thoroughly familiar, with nowhere to remember", "making it all in your mouth", and "thinking carefully" means "seeing what is right and saying what is wrong, and pondering over it repeatedly" and "making its meaning all in your heart". That's probably what it means!