Formant frequency development and gender differences in Mandarin‐learning children before 5 years of age: A longitudinal analysis.

This study is designed to investigate the longitudinal developmental process of vocalic production in Mandarin‐learning children from birth. This current study focuses on the fifth year and the continuity in the process. Major findings are: (1) From three years and six months, the boy subject showed lower vowel formant values, reflecting gender differences in the development of vocal tract. In addition to three years and six months, there was another stage of decrease of frequency at four years and six months in the boy subject. The trend was especially evident in F2 values. (2) The girl subject used more high front rounded vowels /y/, which is the only late‐acquired single vowel. (3) Corner vowels /i, u/ were used more often by the girl subject. (4) Diphthongs continued to show high frequency of occurrence at this stage. (5) The frequency of vowels with nasal endings showed prominent increase at this stage in both genders. However, the girl subject showed more preference in using this vowel category as w...