The language phenomenon of mouth/ teeth/ lip/ tongue-speech exists in Chinese, English and Japanese, cognitive metonymy theory can make up the shortage of traditional rhetoric research, explain this phenomenon well.

• 汉英日三种语言中都存在以“口齿唇舌”指代“言语”的语言现象,认知转喻理论可以弥补传统修辞学研究的不足,对这一语言现象作出较好的解释。