Brian Richards examines variation in children's early language development, with special emphasis on the auxiliary verb. He identifies significant variation both in the age and in the stage of emergence of auxiliaries, and in the rate, style and sequence of subsequent development. He relates some of these aspects to a tendency to acquire the auxiliary holistically, and others to the quality of interaction with the child's partners in conversation. This book will be valuable to all those interested in language acquisition, whether linguists, psychologists, or speech therapists.

Since "Baby Talk" became the subject of research thirty years ago, the linguistic environment of infants and toddlers has been widely studied. This book, as well as being an up-to-date statement of the facts and controversies surrounding "Baby Talk," its nature and likely effects, also examines language acquisition in different cultures and family contexts, typical and atypical learners, and in second and foreign language learners. It has been designed as a sequel to Snow and Ferguson's now famous volume Talking to Children.

Vocabulary richness, including lexical diversity and use of rare words, has an important role in assessing proficiency, diagnosing progress and testing theory in the study of language development. This book reviews different methods for quantifying how vocabulary is deployed in spontaneous speech and writing, before introducing an alternative approach which can assess overall lexical diversity, measure morphology development and compare the development of different word classes. The new approach is illustrated by its application to first and second language learners.

Brian Richards examines variation in children's early language development, with special emphasis on the auxiliary verb. He identifies significant variation both in the age and in the stage of emergence of auxiliaries, and in the rate, style and sequence of subsequent development. He relates some of these aspects to a tendency to acquire the auxiliary holistically, and others to the quality of interaction with the child's partners in conversation. This book will be valuable to all those interested in language acquisition, whether linguists, psychologists, or speech therapists.

Vocabulary richness, including lexical diversity and use of rare words, has an important role in assessing proficiency, diagnosing progress and testing theory in the study of language development. This book reviews different methods for quantifying how vocabulary is deployed in spontaneous speech and writing, before introducing an alternative approach which can assess overall lexical diversity, measure morphology development and compare the development of different word classes. The new approach is illustrated by its application to first and second language learners.