The role of input frequency on the acquisition of English adjectival suffixes by L1 Thai learners

Abstract

This study examined the acquisition of English adjectival suffixes by L1 Thai learners to test whether input frequency, which refers to frequency of occurrences in corpora of English usage (Almulla, 2015; Biber, 1993), influenced the perception of the targeted English adjectival suffixes. Based on the input frequency framework (J. Bybee, 2010; J. L. Bybee & Beckner, 2010; Croft & Cruse, 2004), it was hypothesized that type frequency (suffix frequency) as well as token frequency (word frequency) would have a positive effect on the perception. A Grammaticality Judgement Test which incorporated type and token frequency counts from the MorphoQuantics corpus was administered to 30 intermediate L1 Thai undergraduate students. The results showed that input frequency, both type and token frequency, had an effect on the perception of English adjectival suffixes. Token frequency, however, seemed to play a more significant role in the acquisition possibly because L1 Thai learners were more exposed to the affixed adjectives than to the adjectival suffixes themselves. The results indicated that the learners were likely to acquire and access English adjectives as single units rather than parsing them into derivational morphemes (J. L. Bybee & Beckner, 2010).