One word at a time: the use of single word utterances before syntax. By Lois Bloom. (Janua linguarum, series minor, 154. ) The Hague: Mouton, 1973. Pp. 261. 11. 25.

Children begin saying words sometime around their first birthday and continue to acquire a vocabulary of words until they begin to combine words toward the end of the second year. The study reported here is about the progress of a single child in this period of language development. Observations of the kinds of words she learned, their relative frequency and persistence, and their referential functions revealed developments in cognition—concepts and conceptual relations—that led to discovering linguistic categories and a simple sentence grammar. This research was one of the earliest if not the first study to use video recorded observations in language acquisition research. These observations could be viewed repeatedly to inform the analyses and the conclusions reported here. The carefully annotated transcriptions of the video record at 16+, 19+, 20+, and 22 months are presented in an Appendix.