ABSTRACT
The utterance of a one-word sentence is conceived of as the overt part of a much more complex covert cognitive process. Some cognitive theories are comparable to linguistic theory in that they assume that the one-word sentence expresses an underlying structure of concepts or semantic relationships based on the structure of action. The cognitive approach has dealt with the pragmatic aspects of early sentence production. The cognitive-conceptual explanation would presumably imply that the child has discovered a common content or concept in the various situations in which 'Dodo' is used. The idea that the learning of syntax is based on the child's ability to act and perceive competently is a widely accepted and valuable working hypothesis. The syntactic simplicity of early linguistic forms is only on the surface. In reality every linguistic utterance is embedded in the underlying system of basic syntax.
