S1 Dataset -

The Interface Hypothesis postulates that internal interfaces linking domains within the language system are ultimately acquired at a near-native proficiency level in second language (L2) acquisition. While extensive research in the field of L2 acquisition has demonstrated that L2 learners often fail to completely acquire internal interfaces, the present study adds to this line of research by delving into an understudied phenomenon at the syntax-semantics interface, namely, directions of possession transfer in English Double Object Constructions (DOCs). Specifically, this study focuses on the processing of English DOCs containing verbs with varying or opposing directions of possession transfer. Employing a self-paced reading task and a comprehension task, we examined the performance of 30 native English speakers and 63 first language (L1) Mandarin Chinese learners of English. The findings suggest that L2 learners struggle to fully acquire the intricacies of English DOCs. Additionally, this study reveals that learners encounter challenges in processing English DOCs with left-directional verbs such as buy, compared to those with right-directional verbs such as post and non-directional verbs such as build. This points to an indeterminacy in the processing of the syntax-semantics interface constructions by L2 learners at developmental stages. To account for these findings, we propose an interface indeterminacy account, contending that the indeterminacy in the processing of the syntax-semantics interface constructions by L2 learners stems from the inherent indeterminacy in these constructions. Furthermore, this indeterminacy is likely to be vulnerable to a number of variables, including L1 transfer, learners’ L2 proficiency, and processing resources.

界面假说（Interface Hypothesis）提出，在第二语言（L2）习得中，连接语言系统内部各领域的内部界面最终需以近乎母语的熟练度习得。尽管二语习得领域已有大量研究表明，二语学习者往往无法完全掌握内部界面相关知识，但本研究聚焦句法-语义界面（syntax-semantics interface）这一尚未被充分探讨的现象——即英语双宾语结构（Double Object Constructions, DOCs）中的领属转移方向，为该研究脉络补充了新的实证证据。具体而言，本研究关注带有不同甚至相反领属转移方向动词的英语双宾语结构的加工处理。本研究采用自定步速阅读任务（self-paced reading task）与理解任务，对30名英语母语者与63名汉语为第一语言（L1）的英语学习者的表现进行了考察。研究结果显示，二语学习者难以完全掌握英语双宾语结构的复杂规则。此外，相较于带右向领属转移动词（如post，邮寄）与非方向动词（如build，建造）的结构，学习者在加工带有左向领属转移动词（如buy，购买）的英语双宾语结构时面临更大挑战。这表明二语学习者在发展阶段中，对句法-语义界面结构的加工存在不确定性。为解释上述研究结果，本研究提出界面不确定性解释框架（interface indeterminacy account），认为二语学习者在加工句法-语义界面结构时出现的不确定性，源于这些结构本身固有的不确定性。此外，这类不确定性极易受到诸多变量的影响，包括母语迁移、学习者的二语熟练度与加工资源。