Learning a generative syntax from transparent syntactic atoms in the linguistic input

We examined parents' two-word utterances expressing core syntactic relations in order to test the hypothesis that they may enable children to derive the atoms of hierarchical syntax, namely, the asymmetrical Merge/Dependency relation between pairs of words, and, in addition, to identify variables serving generative syntactic rules. Using a large English-language parental corpus, we located all two-word utterances containing a verb and its subject, object, or indirect object. Analysis showed that parental two-word sentences contain transparent information on the binary dependency/merge relation responsible for syntactic connectivity. The syntactic atoms modelled in the two-word input contain natural variables for dependents, making generalization to other contexts an immediate possibility. In a second study, a large sample of children were found to use the same verbs in the great majority of their early sentences expressing the same core grammatical relations. The results support a learning model according to which children learn the basics of syntax from parental two-word sentences.