Think, Verbalize, then Speak: Bridging Complex Thoughts and Comprehensible Speech

Tony Woo, Sehun Lee, Kang-wook Kim, Gunhee Kim


Abstract
Spoken dialogue systems increasingly employ large language models (LLMs) to leverage their advanced reasoning capabilities. However, direct application of LLMs in spoken communication often yield suboptimal results due to mismatches between optimal textual and verbal delivery. While existing approaches adapt LLMs to produce speech-friendly outputs, their impact on reasoning performance remains underexplored. In this work, we propose **Think-Verbalize-Speak**, a framework that decouples reasoning from spoken delivery to preserve the full reasoning capacity of LLMs. Central to our method is *verbalizing*, an intermediate step that translates thoughts into natural, speech-ready text. We also introduce **ReVerT**, a latency-efficient verbalizer based on incremental and asynchronous summarization. Experiments across multiple benchmarks show that our method enhances speech naturalness and conciseness with minimal impact on reasoning. The project page with the dataset and the source code is available at https://yhytoto12.github.io/TVS-ReVerT.
Anthology ID:
2025.emnlp-main.726
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:
14373–14390
Language:
URL:
https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.726/
DOI:
Bibkey:
Cite (ACL):
Tony Woo, Sehun Lee, Kang-wook Kim, and Gunhee Kim. 2025. Think, Verbalize, then Speak: Bridging Complex Thoughts and Comprehensible Speech. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 14373–14390, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
Think, Verbalize, then Speak: Bridging Complex Thoughts and Comprehensible Speech (Woo et al., EMNLP 2025)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.726.pdf
Checklist:
 2025.emnlp-main.726.checklist.pdf