This is the child's subconscious mind, and the calculation of these problems has been completed. So I wrote this answer. This is a child's carelessness and inattention, and it is not corrected in time, which leads to the child's habit. There is no special way to correct this problem. I can only patiently correct them and tell them that this problem is not 100. How did you come up with this? This is a mistake. Teach by hand, and then let the students you teach teach teach others and snowball. This will not only exercise children, make them proud, but also make them remember this topic forever. Children should be coaxed and praised.