Abstract: There is a common independent construction with speaking, Comment Adjuncts with speaking both in English and Chinese. This paper explores English and Chinese Comment Adjunct contrastively in terms of semantic classification, semantic formation and discourse function. Chinese and English Comment Adjunct with speaking can both be classified into filed type, tenor type and mode type. They can be considered semantically as a project complex sentence, in which the adjunct as the main clause and the proposition as objective clause. Discursively, Comment Adjunct with speaking can functions as the speaker's perspective indicator and attitude engagement as well as discourse cohesion.