Variable production of English object-experiencer psych predicates by Thai EFL first-year university students: an application of the Missing Surface Inflection Hypothesis (MSIH)

The purpose of this research is to investigate the variable production of Object-Experiencer (OE) English psych predicates among 80 L1 Thai EFL first-year university students. Empirical studies have found that psych verbs pose difficulties for learners due to their special quality that does not adhere to standard grammatical norms; specifically, the breach of Thematic Hierarchy or the mapping of thematic roles. The study includes six OE psych verbs: annoy, excite, frighten, interest, shock, and surprise, as well as adjective predicates derived from these verbs in both the present participle (-ing) and past participle (-ed) constructions. All participants were given two written tasks that included a cloze test and a translation test from Thai to English using these predicates, and six individuals were chosen at random to perform the spontaneous oral translation test. Comparisons of the results between the Intermediate and Elementary groups of participants revealed three major findings under the “Missing Surface Inflection Hypothesis” (MSIH), which was used as the primary theoretical framework for the present study. The first research question, that variable production exists in the usage of English OE psych predicates by L1 Thai EFL first-year university students, was answered. Variability was discovered in all three grammatical structures examined and the findings also revealed that the SVO construction may be the most difficult for L1 Thai EFL students to master. Secondly, the second research question was answered: the MSIH is considered a better account than the “Failed Functional Features Hypothesis” (FFFH) for explaining the causes of variable production of L2 functional morphology, based on the evidence from this research. MSIH believes that L2 learners have target-like syntactic representations and that their variable production is due to a failure to map the appropriate morphological forms onto the surface level, rather than a syntactic deficiency. Because the OE psych predicates violate Grimshaw’s (1990) Theta Criterion and Thematic Hierarchy, L1 Thai EFL students misunderstood the linkage of thematic roles to the subject and the object positions. Thirdly, the MSIH goes into greater detail on why variable production happens. Results of the oral live translation by randomized participants indicated that the students knew how to use English OE psych predicates, but they struggled due to extra- or phono-syntactic factors, while providing the correct copular verbs required in the tested grammatical structures.