This document reports an investigation of the developmental changes in the use of certain syntactic structures by white, monolingual, middle class five- and seven-year-olds, and of the differences between the syntax of young children and that used in beginning reading textbooks. Approximately half of the publication presents the methods and results of four separately designed experiments: (1) mass and count noun responses of young children, (2) pronoun case preference of young children, (3) comprehension of time connectives by young children, and (4) comprehension of conditional structures by young children. Other findings reported are that, in the presentation of syntactic structures, reading books followed neither a pedagogically-determined sequence nor one which paralleled the child's language development. It is recommended that new structures be systematically introduced orally, but not be presented in the reading texts until the child can understand and use them. Included are statistical tables, a list of references, and results of other relevant studies. (MF)