To answer the question of how children learn language as quickly as they do with such impoverished input and no explicit instruction, one must assume that a great deal of what children come to demonstrate in terms of their linguistic behavior is the product of grammatical knowledge they bring into this world with them. This study seeks to explain the appearance and then disappearance of certain non-adult like phenomena of child Spanish as a consequence of this in-born knowledge coming on-line. This study will focus on what preliminary studies have shown to be three intriguing phenomena: the early lack of question formation in child Spanish, the early lack of overt subjects in child Spanish as well as the lack of negative imperative verbs in child Spanish. If language acquisition proceeds as quickly and uniformly as it appears to because children are born with highly specified linguistic knowledge of the kind characterized by modern syntactic theory, then the emergence of the elements that syntacticians have argued to be crucial to the three constructions mentioned should have consequences for the development of these three constructions. Concretely, certain grammatical elements (known as functional categories) and the relationships among them are argued to be crucial for all three of the above constructions. Some of these elements appear to be active from the beginning of child Spanish, but others may not develop until after the second birthday. Hence, investigating their development should shed light on the way in which grammar develops in child language as well as the explanatory value of the adult grammatical theories in question. The method used to investigate these developmental consequences is a longitudinal study of three monolingual Spanish-speaking children from the age of 1 year, 6 months until 2 years, 6 months. The subjects will be taped and the tapes will be transcribed and grammatically coded, paying special attention to three constructions in que stion. In this way it will be possible to amass a large amount of monolingual Spanish child data and to study language development during what appears to be the most interesting and volatile period of the development of child Spanish syntax. An important result of this study, in addition to its theoretical ambitions, will be the construction of a rich, longitudinally-collected data base of monolingual child Spanish. At present, no such database is widely available. The resulting data base would be made available to the CHILDES Data Base (MacWhinney and Snow, 1985), thus providing to researchers from many disciplines (Linguistics, Sociology, Anthropology, and Developmental Psychology), an invaluable resource in an extremely widely-spoken language that has been understudied. In the same way that data from the three children from the Brown Corpus (Brown, 1968) have proven to be a virtual gold mine of insight into early child language development, this study aims to furnish the international scientific community with a linguistic resource of substantial value.
