The Acquisition of Focus with Special Reference to the Syntax-Semantics Interface

L1研究：我们进行了一系列实验，以考察幼儿对焦点助词mo“Also”和Dake“Only”的理解。据观察，说日语的儿童对英语和德语习得的反应模式与研究中报道的相似：他们在解释含有焦点表达的句子时不一定依赖句法信息。后续研究发现，儿童的非成人反应模式是相反的，这取决于焦点助词后面是否跟着格助词。为了从同一个孩子身上引出两种相反的反应模式，还进行了额外的实验。最后，基于对日本幼儿自发言语数据的分析，我们认为主语反应(最常见的没有格助词的DAKE模式)受到语序的影响。句法研究：我们提出了这样的假设：MO是一个功能中心语，其焦点目标在Spec位置，而Dake则合并到其目标位置。此外，我们认为派生方法最适合于捕捉焦点表达式的分布。使用这一理论工具，我们分析了(1)Only的词汇语义性质与基于选择功能绑定的组合语义之间的关系；(2)观察到焦点表达可以通过扰乱来避免干预效应。最后，我们认为焦点表达的语义解释所需的结构关系是在显性层面上建立起来的。我们还考虑了在词汇参数化假说的框架内研究儿童焦点表达习得的可能性。

L1 research: We conducted a series of experiments to investigate young children's interpretation of the focus particles mo "also" and dake "only". It was observed that Japanese-speaking children gave similar response patterns to those reported in studies of the acquisition of English and German: they do not necessarily rely on syntactic information in their interpretation of sentences which contain a focus expression. Follow-up sessions revealed that children's non-adult response patterns are reversed depending on whether the focus particle is followed by a Case particle or not. Additional experiments were conducted to elicit the two opposite response patterns from the same child. Finally, we suggested that the subject-oriented response (the most frequent pattern for dake without a Case particle) is influenced by word order, based on an analysis of young Japanese children's spontaneous speech data. Syntactic research: We proposed the hypothesis that mo is a functional head with its focus target in the Spec position, while dake is merged to its target. In addition, we claimed that a derivational approach is most suitable to capture the distribution of focus expressions. Using this theoretical apparatus, we analyzed (1) the relationship between the lexical-semantic property of only and compositional semantics based on choice function binding and (2) the observation that a focus expression can avoid the intervention effect by scrambling. Finally, we argued that the structural relationship required for semantic interpretation of focus expressions is established at the overt level. We also considered the possibility of investigating children's acquisition of focus expressions within the Lexical Parameterization Hypothesis.