Abstract: The supplement sentence of "dou" is a kind of sentence contrary to the traditional Chinese word order, which often appears in daily conversations. Syntactically, the sentence structure is complete before "dou", and there is no shortage of syntactic components; after the supplement, it influenced and changed the nature of the original sentences and the content of exclamation. According to the sequence environment of "dou" supplement sentences, they can be divided into three categories: "initiation-response position" in highly interactive conversation, "initiation position" in highly interactive conversation and "initiation position" in extensible narration. In view of the intensity of mood expression, the mood value of the supplement adverb dou at the end of the sentence is in a continuum of "weak-relatively strong-strong". Through the analysis of the stance triangle theory, it can be seen that the speaker uses the adverb dou at the end of the sentence to express emotion, evaluate stance and implement stance identification.

Key words: dou, supplement, stance expression