When the tongue becomes hard and inflexible, first of all, we have to see if there are local ulcers, swelling or erosion of the tongue, and if ulcers occur after this condition, we have to see what causes them, like this condition will cause local soft tissue hardening and inflexibility when speaking. If there is such a condition, the local soft tissue will be protruded and affect the function of oral articulation or motor function. Secondly, the nerve of the tongue is damaged, which is the sequelae of cranial neurovascular lesion or the neurological symptoms caused by the cervical spine compressing the local nerve. All the above problems need to be ruled out by detailed clinical examination. The existence of these problems can be ruled out by clinical interview, detailed blood routine, blood lipid analysis, and CT examination of cervical spine.