The key aim of this special issue is to make developmental theory proposals concrete enough to evaluate with empirical data. With this in mind, I discuss proposals from the “Universal Grammar + statistics” (UG+stats) perspective for learning several morphology and syntax phenomena. I briefly review why UG has traditionally been part of many developmental theories of language, as well as common statistical learning approaches that are part of UG+stats proposals. I then discuss each morphology or syntax phenomenon in turn, giving an overview of relevant UG+stats proposals for that phenomenon, specific predictions made by each proposal, and what we currently know about how those predictions hold up. I conclude by briefly discussing where we seem to be when it comes to how well UG+stats proposals help us understand the development of morphology and syntax knowledge.

中文翻译：

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形态和句法发展的理论和预测：通用语法+统计方法

本期特刊的主要目的是使发展理论建议足够具体，以用经验数据进行评估。考虑到这一点，我讨论了“通用语法+统计”的建议（UG+统计) 学习几种形态和句法现象的视角。我简要回顾了为什么 UG 传统上一直是许多语言发展理论的一部分，以及作为 UG+stats 提案一部分的常见统计学习方法。然后，我依次讨论每种形态或句法现象，概述针对该现象的相关 UG+stats 提案，每个提案做出的具体预测，以及我们目前对这些预测如何成立的了解。最后，我简要讨论了 UG+stats 提案如何帮助我们理解词法和句法知识的发展。