In her Beijing lectures, Melissa Bowerman presents a lucid introduction and account of her research on a range of topics: how children acquire the semantics of spatial terms, how they construct categories and acquire the semantics of nouns, and how they master the semantics of verbs in early language acquisition. Bowerman also covers the learning of argument structure and expressions of end-state, with special attention to the adult speech that guides children, and hence also the role of typology in acquisition; how cross-linguistic variation affects, for example, how speakers represent 'cutting' and 'breaking' in different languages, and the relation of the Whorfian Hypothesis to cross-linguistic variations in the semantics of languages. Bowerman's over-riding concern throughout is with how children come to master the first language being spoken to them by their parents and caregivers.