TenseLoC: Tense Localization and Control in a Multilingual LLM
Ariun-Erdene Tumurchuluun, Yusser Al Ghussin, David Mareček, Josef Van Genabith, Koel Dutta Chowdhury
Abstract
Multilingual language models excel across languages, yet how they internally encode grammatical tense remains largely unclear. We investigate how decoder-only transformers represent, transfer, and control tense across eight typologically diverse languages: English, German, French, Italian, Portuguese, Hindi, Spanish, and Thai. We construct a synthetic tense-annotated dataset and combine probing, causal analysis, feature disentanglement, and model steering to LLaMA-3.1 8B. We show that tense emerges as a distinct signal from early layers and transfers most strongly within the same language family. Causal tracing reveals that attention outputs around layer 16 consistently carry cross-lingually transferable tense information. Leveraging sparse autoencoders in this subspace, we isolate and steer English tense-related features, improving target-tense prediction accuracy by up to 11%% in a downstream cloze task.- Anthology ID:
- 2025.mrl-main.17
- Volume:
- Proceedings of the 5th Workshop on Multilingual Representation Learning (MRL 2025)
- Month:
- November
- Year:
- 2025
- Address:
- Suzhuo, China
- Editors:
- David Ifeoluwa Adelani, Catherine Arnett, Duygu Ataman, Tyler A. Chang, Hila Gonen, Rahul Raja, Fabian Schmidt, David Stap, Jiayi Wang
- Venues:
- MRL | WS
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 243–264
- Language:
- URL:
- https://preview.aclanthology.org/ingest-emnlp/2025.mrl-main.17/
- DOI:
- Cite (ACL):
- Ariun-Erdene Tumurchuluun, Yusser Al Ghussin, David Mareček, Josef Van Genabith, and Koel Dutta Chowdhury. 2025. TenseLoC: Tense Localization and Control in a Multilingual LLM. In Proceedings of the 5th Workshop on Multilingual Representation Learning (MRL 2025), pages 243–264, Suzhuo, China. Association for Computational Linguistics.
- Cite (Informal):
- TenseLoC: Tense Localization and Control in a Multilingual LLM (Tumurchuluun et al., MRL 2025)
- PDF:
- https://preview.aclanthology.org/ingest-emnlp/2025.mrl-main.17.pdf