My interests lie in the logical problem of language acquisition and syntactic/semantic acquisition, with special reference to Mandarin-speaking and Cantonese-speaking children. My recent research has been on quantifier scope in Chinese datives, Cantonese A-quantifiers, and syntactic change in Cantonese. Below are topics I have worked on:

(a) The acquisition of quantifier scope in Mandarin-speaking children, examining children’s knowledge of the isomorphic principle in the mapping between logical form and syntax, and how that knowledge may be constrained by locality principles, quantifier type, and the thematic hierarchy;

(b) The development of linguistic knowledge in Mandarin-speaking children in the transition from babbling to syntax, focusing on issues such as lexical spurt, the onset of syntactic categories, word order and argument structure; the development of preschoolers’ competence with respect to classifiers and nominal structure, A-quantifiers and negation;

(c) Syntactic and semantic development in Cantonese preschoolers, with respect to word order and argument structure, questions, pro-drop, sentence-final particles, nominal structure and referentiality, additive/restrictive focus, and A-quantifiers;

(d) The relationship between language acquisition and language change, as seen from ongoing changes in the structure of the noun phrase in modern-day Hong Kong Cantonese.

A large part of my work is based on longitudinal child-language data. Along with colleagues from Hong Kong Polytechnic University and the University of Hong Kong (Colleen Wong and Sam Leung), I developed the Hong Kong Cantonese Child Language Corpus (CANCORP). Collaborating with researchers in China (Yang Xiaolu of Tsing Hua University and the late Professor Fang Li of Beijing Language and Culture University), I have built a Chinese Early Language Acquisition corpus (CELA) of children in Beijing, Changsha and Hong Kong, investigating how Chinese children acquire the core properties of the target languages from infancy to two years of age.