This study investigates the comprehension process of second language (L2) English idioms, focusing on decomposability and construal. Based on their interlingual formal similarity and construal properties, English idioms were classified into four types: cognate, false cognate, pragmatic, and English-only idioms. Self-reported perceptual data from 50 Korean undergraduate learners revealed that, regardless of idiom type, learners consistently experienced greater perceived difficulty in construal ratings than in word-level decomposability ratings. This asymmetry was most pronounced in English-only idioms. In the case of false cognate idioms, learners showed relatively low perceived difficulty, suggesting a pattern of misguided confidence resulting from the inappropriate activation of L1-based conceptual resources. These findings indicate that idiomatic transparency cannot be reduced to decomposability alone and should be understood as a multi-layered construct.
Hyechong Park (Tue,) studied this question.