How, precisely, does a child acquire speech? Imitation? Innate capacity? And how do researchers test a child's developing capacities? Like other books in this series, this explores crucial questions in terms accessible to parents, without bogging down in the theoretical mazes of professional linguists. And, anticipating the worst, its authors warn that making parents self-conscious about teaching their children to talk--a quintessentially spontaneous process--is not their intent. Peter de Villiers and Jill de Villiers, authors of the more technical Language Acquisition, focus on language development, its patterns and areas of idiosyncracy, in an authoritative, instructive manner. Normal infants, they demonstrate, are sensitive to small sound differences at an early age and babble predictably--all around the world. Children perceive differences before they can duplicate them and, at each stage, are generally consistent in their errors. Adults help out: mothers tend to accommodate their utterances to a child's level of understanding, and families can provide an environment which facilitates language acquisition. Nonetheless, the sequence of mastery is quite similar for all children--plurals before tenses, for example, and passive sentences later still. By age four most children can use personal pronouns, a language skill autistic children rarely master. In other words, parents can encourage expression but physical and intellectual determinants also operate. The authors explain the work of Roger Brown and other key figures in the field, draw insights from work with exceptional children, and recommend specific strategies for parents.