This study examined the acquisition of numeral classifiers in 120 monolingual Japanese children. Previous research has argued that the complex semantic system underlying classifiers is late acquired. Thus, we set out to determine the age at which Japanese children are able to extend the semantic properties of classifiers to novel items/situations. Participants completed a comprehension task with a mouse-tracking extension and a production task with nonce and familiar items. While the comprehension results showed ceiling effects on familiar and nonce items, age significantly modulated a difference in accuracy between familiar and nonce items in the production task. The findings suggest that the acquisition of the underlying semantic system is acquired much earlier than previously argued. Previously attested issues with Japanese classifier production in young(er) children are more likely to reflect accessing difficulties than indexing the underlying grammatical competence of the classifier system.

中文翻译：

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日语数字分类词语义的习得：废话的方法论价值

这项研究调查了 120 名只会说一种语言的日本儿童的数字分类能力习得情况。先前的研究认为，分类器背后的复杂语义系统是后来获得的。因此，我们着手确定日本儿童能够将分类器的语义属性扩展到新项目/情况的年龄。参与者通过鼠标跟踪扩展完成了理解任务，并通过随机数和熟悉的项目完成了生产任务。虽然理解结果显示对熟悉和随机数项目的上限效应，但年龄显着调节了生产任务中熟悉和随机数项目之间的准确性差异。研究结果表明，底层语义系统的获得比之前认为的要早得多。先前证实的幼儿日语分类词生成问题更可能反映了访问困难，而不是索引分类词系统的潜在语法能力。