Nominal-level word order variations at the interfaces: A study of adult second language acquisition of Chinese

It is commonly held that the language faculty consists of modules like syntax, semantics, morphology, etc., and that the interactions between linguistic modules as well as those between linguistic modules and language-external factors (e.g. discourse, cognitive domain) – referred to as ‘interfaces’ in the literature – are grammatically regulated (Lambrecht 1994; Choi 1996; Chomsky 2001; Jackendoff 2002, 2007; Reinhart 2006; Ramchand and Reiss 2007). Such a modular view of language has brought about non-trivial implications to second language acquisition research since the late 2000s, with a famous hypothesis proposed being the Interface Hypothesis. This hypothesis subcategories the interface into the internal interface, which pertains to mappings between linguistic modules (e.g. syntax-semantics), and the external interface, which connects linguistic modules with language-external domains (e.g. syntax-discourse). The core assumption is that while it is possible for advanced adult second language (L2) learners to acquire internal interface knowledge to a native-like level, external interface knowledge is more prone to non-native optionality (Sorace and Filiaci 2006; Tsimpli and Sorace 2006; Slabakova 2008; Sorace and Serratrice 2009; White 2009).
In spite of a fruitful body of research generated by the Interface Hypothesis, prior studies mainly focused on clausal-level phenomena in Indo-European L2s (except for, to the best of our knowledge, Yuan’s (2013) research on L2 Chinese and Laleko and Polinsky’s (2016) study on L2 Japanese and Korean). Also, the empirical results to date have still been highly mixed (Hopp 2007; Slabakova and Ivanov 2011; Ivanov 2012; Donaldson 2012; Leal 2016). The present study is aimed to advance the discussion in this area, and re-examine the Interface Hypothesis via investigating the adult L2 acquisition of the word order variation of numeral classifier indefinites at the syntax-semantics and syntax-discourse interfaces in L2 Chinese via rigorous research paradigms involving the online task. Specifically, the study addresses the following two research questions (RQs): (1) Can advanced adult L2 Chinese learners acquire the nominal-level syntax- semantics and syntax-discourse interface knowledge about the word order variation to a native- like level? (2) Does L2 Chinese proficiency affect adult L2 Chinese learners’ acquisition of the target alternation at the syntax-semantics and syntax-discourse interfaces?
To answer the above RQs, a computerized acceptability judgment task (AJT) was administered to collect data in accuracy and reaction times. The participants of the study were 41 adult native Korean learners of Chinese (who were further divided into an advanced group of 18 and an intermediate group of 23) and 15 adult native speakers of Chinese. 120 stimuli were presented in the audio-visual form on a stand-alone computer program designed for the study, and the AJT was administered to each participant one by one to record their responses and reaction times (recorded as the latency between the offset of the expression and onset of key pressing in milliseconds). The findings suggested that the simple internal versus external interface dichotomy may not suffice to account for the acquisition difficulty and processing costs of different linguistic properties in L2 acquisition. Finally, the study pointed out several promising directions for further research concerning L2 acquisition at the interfaces. Copyright © 2019 ACBM.