Explicit Learning and the LLM in Machine Translation

Malik Marmonier, Rachel Bawden, Benoît Sagot


Abstract
This study explores an LLM’s ability to learn new languages using explanations found in a grammar book—a process we term “explicit learning.” To rigorously assess this ability, we design controlled translation experiments between English and constructed languages generated—through specific cryptographic means—from Latin or French. Contrary to previous studies, our results demonstrate that LLMs do possess a measurable capacity for explicit learning. This ability, however, diminishes as the complexity of the linguistic phenomena to be learned increases. Supervised fine-tuning on ad hoc chains of thought significantly enhances LLM performance but struggles to generalize to typologically novel or more complex linguistic features. These findings point to the need for more diverse training sets and alternative fine-tuning strategies to further improve explicit learning by LLMs, benefiting low-resource languages typically described in grammar books but lacking extensive corpora.
Anthology ID:
2025.emnlp-main.1599
Volume:
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Month:
November
Year:
2025
Address:
Suzhou, China
Editors:
Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
Venue:
EMNLP
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
31360–31410
Language:
URL:
https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.1599/
DOI:
Bibkey:
Cite (ACL):
Malik Marmonier, Rachel Bawden, and Benoît Sagot. 2025. Explicit Learning and the LLM in Machine Translation. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 31360–31410, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
Explicit Learning and the LLM in Machine Translation (Marmonier et al., EMNLP 2025)
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https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.1599.pdf
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