Closely related to psycholinguistics is sociolinguistics, which has also enhanced my research in language variation and change and language teaching. As a child growing up in Hong Kong, I was raised in a triglossic environment (Cantonese, Mandarin, English) and was made acutely aware of our (socio-)linguistic norms (code-switching, interference, domains etc) from a very young age. Since studying languages and linguistics, I was always interested in finding out how languages were used not only within purely formal grammatical contexts but also within a sociohistorical background. Below is an outline in my experience in sociolinguistics in chronological order:
In my undergraduate studies at the University of Oxford, I studied historical phylogeny in Indo-European linguistics, and at the University of Manchester, I submitted two research papers on language contact, one for Professor Yaron Matras' taught course 'Language Contact' and the other for my research course 'Language Contact in the Roman Empire' with Professor David Langslow. I also participated in Dr Maciej Baranowski's sociolinguistic group project on Mancunian English dialects and learnt the practical aspects of conducting sociolinguistic experiments. I then studied dialectology with Professor Dennis Preston at the Linguistic Society of America (LSA) Summer Institute 2011 and gave a presentation on Indo-European phylogeny, and in 2012 I presented a poster on the Italo-Celtic question at the University of Rennes as well as took part in the Leiden Indo-European Summer School. At the Linguistic Society of America (LSA) Summer Institute 2013, I audited 'Syntactic Variation: Sentences and Utterances' given by Professor Ralph Fasold, 'Attitudes, Ideologies, Variation and Change' by Professor Dennis Preston, and 'Sentences and the Social' by Professor Julie Boland and Dr Lauren Squire, which greatly improved my understanding of modern sociolinguistic theory and its interface with formal syntax. At the University of York, I audited all the postgraduate sociolinguistics seminars given by Professor Paul Kerswill, Dr Andrew Macfarlane, Dr Dom Watts and Dr Carmen Llamas, which dealt mainly with non-standard varieties of English in modern Britain. Furthermore, I had numerous conversations with Dr Márton Sóskuthy and Professor Paul Foulkes on issues in sociophonetics, which tied in with my work on frequency and weakening effects in grammaticalization. Due to my secondary interests in sociolinguistics, I have contributed Opinion articles on Cantonese and Mandarin in modern-day Hong Kong and China on Asia Times Online.
It might strike some people as strange that a formal linguist interested in formal syntax would also be interested in sociolinguistics, but my interests in human language stretch far beyond its grammatical aspects as they also include the external aspects of language use. Sociolinguistics is also indispensable for my research in historical linguistics, as language variation and change are essential in any historical analyses and understanding. Indeed, my own research on syntactic change takes into account the frequencies and variations of grammatical forms in grammaticalization, so my pursuit of modern sociolinguistic theory is not only not detrimental to my main research in formal syntactic change but also strongly and healthily complementary. Human language is fascinating, not only in its formal aspects but also in its social uses. Any attempt to mutually exclude one from the other is simplistic and naive.