This step was much slower than expected.
Deaf and mute students also fall into two categories. One is that there are physiological problems with the vocal organs, making them unable to speak.
The other category consists of some congenitally deaf-mute students who actually have no problem with their vocal organs but cannot speak because they cannot hear and therefore have not learned to speak.
These students, by relying on [Eight Sides] to hear sounds again, have already regained their language ability with the help of teachers and parents, even though they can only make meaningless sounds like "ah ah ah" at the beginning.
After re-adjustment, the class is composed of students with congenital problems in their vocal organs, such as central language disorders, tongue-tie abnormalities, genetic factors, and those who have lost their language abilities due to accidents.
The improved [Eight Sides] can now solve this problem.