This paper explores the topic constructions in conversation based on natural spoken Chinese data. It finds that there are three types of topic constructions( henceforth,TC),w hich are,the single party building TC,the cooperatively building TC and the competitively building TC. The topic construction presents three features in regard to its placement: the complexity of the topic’s TCU-initial-position placing,the extendability of the turncrossing comment,as w ell as the completeness of the topic construction w ithin a turn,w hich exerts interac...