| Two views on the nature of children’s syntactic acquisition exist in previous studies.One argues that children’s syntactic development is rule-based,while the other asserts that it is usage-based.Although extensive research findings have contradicted the rule-based view,there is no definitive conclusion on this controversy.The present study,based on ten Mandarin and English preschool children’s natural conversations,examines the acquisition and development of existential constructions,and answers four research questions:(1)What are the syntactic features of Chinese and English children’s existential constructions?(2)What are the semantic features of Chinese and English children’s existential constructions?(3)What are the pragmatic functions of Chinese and English children’s existential constructions?(4)What are the similarities and differences in Chinese and English children’s production of existential constructions in spatial and temporal dimensions?Data analysis reveals that the syntactic structure of the Chinese and English children’s existential constructions exhibits a trend from syntactic fragments to complete structures.A complete existential construction must have three components:a locative noun,an existential verb,and an existential object.Initially,Chinese and English children’s existential constructions only had one component,either an existential object or a locative segment.As they grow older,the existential constructions produced contained two components,an existential verb + an existential object,or an existential verb + a locative segment.Finally,children’s syntactic structures had three components,i.e.,locative segment + existential verb + existential object,and the structure gradually becomes complete.At the semantic level,Chinese and English children first mastered the existential sense of the existential construction,followed by the appearance sense,and finally the disappearance sense.At the pragmatic level,Chinese children first mastered the ontological function of existential constructions,which describes facts or the environment,and then used existential constructions to express requests or explain reasons.English children,like Chinese children,initially mastered the ontological function of existential constructions,then the function of indirect request,and finally the attention-attracting function.Overall,the syntactic,semantic,and pragmatic features of existential constructions produced by Chinese and English children are similar in terms of their longitudinal development,with significant differences in details on synchronic level.The study indicates that the acquisition and development of Chinese and English children’s existential constructions follow certain patterns,mainly reflected in three aspects.First,the syntactic structure of Chinese and English children’s production of existential constructions is not the same at all stages,from syntactic fragments to the complete existential structure,indicating that the development of their syntactic structures appears to be a dynamic process.Second,the gradual increase in the mean sentence length of the children’s existential constructions seems to suggest that the acquisition of this construction is a gradual process.Finally,the children use the basic forms of existential constructions(“有” and “there be” constructions)most frequently,and the types of the components(locative segment,existential verbs,existential objects)in these three forms are also the most diverse,indicating that the greater the frequency of children’s use of a particular structure,the higher their mastery level of that structure.In summary,the acquisition and development of Chinese and English children’s existential constructions reflects general cognitive processes such as intention reading,imitative learning,and structural combination,which is more consistent with the usage-based view of language acquisition and appears not to be a process and outcome of rule abstraction. |