Origin of Modern Chinese pragmatic markers bushi: Negative copula or negative adjective?

Axelsson, 2011, A cross-linguistic study of grammatically-dependent question tags: data and theoretical implications, Stud. Lang., 35, 793, 10.1075/sl.35.4.02axe Blakemore, 2002 Chang, 2006 Chen, 2018, (Inter)subjectification at the left and right periphery: deriving Chinese pragmatic marker bushi from the negative copula, Lang. Sci., 66, 83, 10.1016/j.langsci.2018.01.002 Diessel, 1999 Dong, 2004, Shi de jinyibu yufahua: you xuci dao cinei chengfen “是”的进一步语法化:由虚词到词内成分, Dangdai Yuyanxue 当代语言学, 6, 35 Feng, 2008, Pragmatic markers in Chinese, J. Pragmat., 40, 1687, 10.1016/j.pragma.2008.05.012 Fraser, 1996, Pragmatic markers, Pragmatics, 6, 167, 10.1075/prag.6.2.03fra Fraser, 2006, Towards a theory of discourse markers, 189 Fraser, 2009, An account of discourse markers, Int. Rev. Pragmat., 1, 293, 10.1163/187730909X12538045489818 Hansen, 2005, The evolution of pragmatic markers, J. Hist. Pragmat., 6, 177, 10.1075/jhp.6.2.02mos Heine, 2002 Hengeveld, 1992 History Department of Peking University 北京大学历史系, 1979 Hong, 1964, Mengzi li de shi zi yanjiu 《孟子》里的“是”字研究, Zhongguo Yuwen 中国语文, 133, 285 Hsin, 2016, An analysis of Chinese tag questions with a cross-linguistic comparison to English tags, Taiwan J. Linguist., 14, 59 Hsu, 2008, The sentence-internal topic and focus in Chinese, vol. 2, 635 Hu, 2014, Huayu biaoji budui de gongneng fenxi 话语标记“不对”的功能分析, Hanyu Xuexi 汉语学习, 3, 104 Huang, 1988, On be and have in Mandarin Chinese, Bull. Inst. Hist. Philol., 59, 43 Jarvis, 2011 Liang, 2012, Hanyu xici shi de xingcheng jizhi 汉语系词“是”的形成机制, Yuyan Yanjiu 语言研究, 4, 39 Liu, 2005, Zuowei huayu biaojiyu de bushi 作为话语标记语的“不是”, Yuyan Jiaoxue yu Yanjiu 语言教学与研究, 6, 23 Liu, 2011, X+bu wenju shuolue“X+不”问句说略, Baoding Xueyuan Xuebao 保定学院学报, 24, 96 Long, 2013, On the formation of Modern Chinese VdeO focus clefts, Acta Linguist. Hung., 60, 409, 10.1556/ALing.60.2013.4.2 Long, 2018, Modern Chinese confirmative shi: auxiliary or adverb?, Funct. Lang., 24, 294, 10.1075/fol.15018.lon Maiden, 2007 Mazeland, 2010, Doing confirmation with ja/nee hoor: sequential and prosodic characteristics of a Dutch discourse particle, 161 Paul, 2008, Shi..de focus clefts in Mandarin Chinese, Linguist. Rev., 25, 413 Proudfoot, 2005 Schiffrin, 1987 Shi, 1994, The nature of Chinese emphatic sentences, J. East Asian Linguist., 3, 81, 10.1007/BF01733150 Shi, 1997, Biao fanwen de bushi 表反问的“不是”, Zhongguo Yuwen 中国语文, 1, 25 Soh, 2007, Ellipsis, last resort, and the dummy auxiliary shi ‘be’ in Mandarin Chinese, Linguist. Inquiry, 38, 178, 10.1162/ling.2007.38.1.178 Sun, 2006 Svennevig, 2007, “Ikke sant?” As a response token in Norwegian conversation, 175 Thokchom, 2017, Tag questions in Manipuri and German, Lang. India, 17, 163 Traugott, 2012, Intersubjectification and clause periphery, 7 Traugott, 2016, On the rise of types of clause-final pragmatic markers in English, J. Hist. Pragmat., 17, 26, 10.1075/jhp.17.1.02tra Urbanik, 2019, Managing contingencies in requests: the role of negation in Norwegian interrogative directives, J. Pragmat., 139, 109, 10.1016/j.pragma.2018.10.014 Wang, 1937, Zhongguo wenfa zhong de xici 中国文法中的系词, 212 Wang, 1989 Wang, 2017, Juweibushide laiyuan, gongneng jiqi cihuihua 句尾“不是”的来源,功能及其词汇化, Yuyan Jiaoxue yu Yanjiu 语言教学与研究, 6, 53 Wei, 2010, A movement and resumption approach to VP-ellipsis in Mandarin Chinese, Tsing Hua J. Chin. Stud., 40, 113 Xiao, 2017, Yuanchu shi daici shuo de laiyou jiqi mianlin de kunjing 原初“是”代词说的来由及其面临的困境, Jiangxi Keji Shifan Daxue Xuebao 江西科技师范大学学报, 1 Xu, 2003, Remarks on VP-ellipsis in disguise, Linguist. Inquiry, 34, 163, 10.1162/ling.2003.34.1.163 Yen, 1986, The origin of the copula shi in Chinese, J. Chin. Linguist., 14, 227 Yin, 2011, Shuo huayu biaoji bushi说话语标记“不是”, Hanyu Xuexi 汉语学习, 1, 36 Zhan, 2017, The constructionalization of a set of Chinese connectives, J. Chin. Linguist., 46, 104 Zhan, 2015, The constructionalization of the Chinese cleft construction, Stud. Lang., 39, 459, 10.1075/sl.39.2.06zha Zhan, 2019, The development of the Chinese copula shì construction: a diachronic constructional perspective, Funct. Lang., 26, 139, 10.1075/fol.16001.zha Zipf, 1949