“…Some individual differences with particularly good explanatory power in L2 acquisition include age (Pfenninger and Singleton, 2017), aptitude (Wen et al, 2017), motivation (Csizér, 2017), and working memory (Juffs and Harrington, 2011). The role of working memory, for example, has been demonstrated separately for vocabulary (e.g., Hummel, 2009; Martin and Ellis, 2012; Malone, 2018; Yang et al, 2018) and grammar learning (Tagarelli et al, 2015, 2016; Denhovska and Serratrice, 2017; Indrarathne and Kormos, 2017). Further, several studies have indicated that the effect of working memory may depend on exposure condition, with working memory playing a more important role under explicit exposure conditions than in implicit conditions (Tagarelli et al, 2011; Grey et al, 2015; Linck and Weiss, 2015; Indrarathne and Kormos, 2017).…”