Abstract
(type = abstract)
Imperatives are one of the three major clause types of human language, along with declaratives and interrogatives (Aikhenvald, 2010; Alcázar & Saltarelli, 2014; Portner, 2016). Imperatives are usually employed to express commands, but they can convey other meanings such as entreaties, requests, advice or instructions (Aikhenvald, 2010). The current study investigates the acquisition of syntactic and morphological properties of imperatives in Spanish in order to test previous proposals on the order of acquisition of language components for L2 learners and heritage speakers. Moreover, this study examines whether the acquisition of this structure is modulated by extra-linguistic factors (e.g., proficiency in Spanish, age of onset of acquisition of Spanish and English, and patterns of language exposure and use) and by lexical frequency (i.e., how frequently a given lexical item appears in the input).
Previous proposals on the order of acquisition of language components in L2 learners agree on that morphology is the most challenging language component to acquire for L2 learners (Jiang, 2000; Lardiere, 2008, 2009; Slabakova, 2013). A similar focus on the difficulty to acquire morphology is found in proposals on heritage language acquisition and maintenance (Putnam & Sánchez, 2013). This study aims to test the validity of these proposals by examining the acquisition of imperatives in Spanish, which present a complex syntax and a relatively poor morphology (Alcázar & Saltarelli, 2013; Ezeizabarrena, 1997; Rivero & Terzi, 1995). Furthermore, this study also tests previous approaches that underline the importance of language activation in the acquisition of second and heritage languages (Gollan, Weissberger, Runnqvist, Montoya, & Cera, 2012; Paradis, 1993; Putnam & Sánchez) by examining the role of extra-linguistic factors that measure the activation of their non-dominant language, Spanish, throughout their lives. Along the lines of language activation, this study also investigates the effects of lexical frequency on the acquisition of morphology. Specifically, lexical frequency is used as a proxy for language activation: more frequent lexical items are more frequently activated in the bilingual mind for production and comprehension purposes (Putnam & Sánchez, 2013).
A group of L2 learners (n = 51) and heritage speakers (n = 58) of varied proficiency levels completed an elicited production task, an acceptability judgment task, and a self-reported lexical frequency test, as well as several screening tasks and tests. A group of 12 Spanish-dominant bilinguals and 20 Spanish instructors served as comparison groups for the heritage speakers and the L2 learners, respectively. The results, which are not consistent with previous second language proposals and hypotheses (Jiang, 2000; Lardiere, 2008, 2009; Slabakova, 2013), show that L2 learners acquire some functional morphology, namely number morphology (e.g., ¡mira! ‘(singular you) Look!’ vs ¡miren! ‘(plural you) Look!’), which is less challenging than purely syntactic operations, as seen in clitic placement. The heritage speakers, on the other hand, present a more stable syntax than morphology, consistently with Putnam and Sánchez (2013). Additionally, language activation, as measured by proficiency and age of onset of acquisition of Spanish and English, has an effect on the acquisition of the properties under examination. On the other hand, patterns of language exposure and use, and lexical frequency (e.g., ¡mira! ‘Look!’ vs ¡cose! ‘Sew!’) only play a role in the acquisition of morphology in heritage speakers, but not in L2 learners. These findings support claims that heritage language activation is crucial for its acquisition and maintenance (Putnam & Sánchez, 2013) and that heritage speakers present differential access to their grammatical knowledge as a function of lexical frequency (Pérez-Cortés, Putnam, & Sánchez, 2019).
The contributions of this study are threefold: First, this is the first study that investigates the acquisition of Spanish imperatives in L2 learners and heritage speakers. Second, this study challenges previous literature (Lardiere, 2008, 2009; Slabakova, 2013, 2019) by finding that L2 learners acquire functional morphology earlier than a purely syntactic operation. Third, this is the first study that found lexical frequency effects in the acquisition of morphology with morphologically regular verbs in heritage speakers.