Can you map it to English? The Role of Cross-Lingual Alignment in the Multilingual Performance of LLMs
Kartik Ravisankar, HyoJung Han, Sarah Wiegreffe, Marine Carpuat
Abstract
Large language models (LLMs) can answer prompts in many languages, despite being trained predominantly on English; yet, the mechanisms driving this generalization remain poorly understood. This work asks: How does an LLM’s ability to align representations of non-English inputs to English impact its performance on natural language understanding (NLU) tasks? We study the role of representation alignment in instance-level task decisions, complementing prior analyses conducted both at the language level and task-independently. We introduce the Discriminative Alignment Index (\DALI) to quantify instance-level alignment across 24 languages other than English and three distinct NLU tasks. Results show that incorrect NLU predictions are strongly associated with lower representation alignment with English in the model’s middle layers. Through activation patching, we show that incorrect predictions in languages other than English can be fixed by patching their parallel English activations in the middle layers, thereby demonstrating the causal role of representation (mis)alignment in cross-lingual correctness.- Anthology ID:
- 2026.eacl-long.225
- Volume:
- Proceedings of the 19th Conference of the European Chapter of the Association for Computational Linguistics (Volume 1: Long Papers)
- Month:
- March
- Year:
- 2026
- Address:
- Rabat, Morocco
- Editors:
- Vera Demberg, Kentaro Inui, Lluís Marquez
- Venue:
- EACL
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 4854–4872
- Language:
- URL:
- https://preview.aclanthology.org/ingest-eacl/2026.eacl-long.225/
- DOI:
- Cite (ACL):
- Kartik Ravisankar, HyoJung Han, Sarah Wiegreffe, and Marine Carpuat. 2026. Can you map it to English? The Role of Cross-Lingual Alignment in the Multilingual Performance of LLMs. In Proceedings of the 19th Conference of the European Chapter of the Association for Computational Linguistics (Volume 1: Long Papers), pages 4854–4872, Rabat, Morocco. Association for Computational Linguistics.
- Cite (Informal):
- Can you map it to English? The Role of Cross-Lingual Alignment in the Multilingual Performance of LLMs (Ravisankar et al., EACL 2026)
- PDF:
- https://preview.aclanthology.org/ingest-eacl/2026.eacl-long.225.pdf