Mio Ohashi
2026
LLM-based Literal Example Generation for Japanese Multiword Expressions
Mio Ohashi | Hajime Kiyama | Zhidong Ling | Mamoru Komachi
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (ACL 2026)
Mio Ohashi | Hajime Kiyama | Zhidong Ling | Mamoru Komachi
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (ACL 2026)
We investigate whether large language models (LLMs) can generate literal usage examples for Japanese multiword expressions (MWEs), whose literal readings are structurally low-frequency in available corpora.Prior work on MWEs has largely focused on detecting idiomatic usages in context, leaving literal usages underrepresented particularly for Japanese MWEs whose literal readings are rare and structurally diverse.Because literal readings are rarely attested in corpora, we design a lexicon-grounded setup that uses corpus non-literal usages as contrastive cues for controlled prompting. We evaluate the generated sentences using automatic literalness judgments and human literalness judgments, together with manual inspection.Our results show that providing contrastive non-literal information stabilizes literal generation and improves quality compared with prompts that include only literal information or no hints. In addition, we conduct an LLM-based understanding test that compares model predictions of literal and idiomatic plausibility with human judgments.The results indicate that the model aligns more closely with human judgments for idiomatic interpretations than for literal ones, highlighting the relative difficulty of modeling literal readings of MWEs.The study demonstrates that LLMs can complement existing resources by supplying frequency-independent literal examples and offers a controlled framework for examining contextual meaning understanding of Japanese MWEs.