After the voice has completely changed from a child’s voice to an adult’s voice, the voice change period is over. As the development of youth kicks in and the gonads begin to awaken and secrete a large amount of sex hormones, changes in the structure of the larynx occur for both boys and girls, with the larynx lengthening and widening significantly and the vocal folds elongating. Boys will tend to have a low voice and even some slight inflammation of the vocal cords, while girls will have changes in their vocal cords and their voices will not be the same as a child’s voice. Usually most boys and girls appear at the age of 12-14, and most of them experience about a year, but of course there are individual differences, some of them are only about half a year, and some even extend to 2-3 years. And the length of the voice change period and the geographical relationship, like the southern children’s voice change period is relatively short, while the north takes a relatively long time. There are three stages of voice change, some changes are not felt at the beginning, but at the third stage, the voice completely changes from a child’s voice to an adult voice. During this period, you should pay attention to protect your vocal cords and not to speak loudly for a long time. In addition, you should not eat any spicy or irritating food, but eat more vegetables and fruits, and take a good rest to pass the voice change period smoothly.