This collection of studies is divided into four parts. Part one is concerned with aspects of maternal communication as it relates to regulative and instructional contexts. Part two focuses on aspects of the speech of five year olds, with Hawkins examining choices within the nominal group, Turner and Pickvance examining expressions of uncertainty and tentativeness, and Robinson and Creed describing an experiment to test the effects of a language program designed by D. M. and G. Gahagan. Part three examines aspects of the speech of seven year olds: Hawkins analyzes social class differences in the use of hesitation in speech; Robinson analyzes the answering behavior of mother and children, showing the interrelationship between styles; and Turner compares the speech of five-year-old children with the same children's speech at seven years of age. Hansan and Cook in part four distinguished between code, register, and social dialect and review a range of studies which focus upon the study of social control and socialization within the family. Finally, Halliday explores his approach to the child's acquisition of the functions of language. (HOD)