Xu, Kang2022-03-182022-03-182022-032371-2643http://hdl.handle.net/1880/114492https://dx.doi.org/10.11575/PRISM/39652Mandarin sentence-final particles have been analyzed uniformly as sentence-final complementizers by a group of researchers (Paul & Pan, 2017; Pan, 2019). However, in the present paper, I draw evidence from co-occurring sentence-final particles to demonstrate that in Mandarin, sentence-final particles must co-occur in a fixed order. This observation casts doubts on the assumption that these particles are complementizers because treating them as complementizers does not explain why they appear in a fixed order. Following Wiltschko (2020), I propose that these particles belong to different categories of the interactional structure. I focus my discussion on three representative particles, namely, ne 呢 , me 么 and ha 哈 . An analysis that assumes an interactional structure above CP can account for some poorly understood co-occurrence restrictions among these particles.engMandarin sentence-final particlesinteractional structureworking paper