COAS2W: A Chinese Older-Adults Spoken-to-Written Transformation Corpus with Context Awareness

Spoken language from older adults often deviates from written norms due to omission, disordered syntax, constituent errors, and redundancy, limiting the usefulness of automatic transcripts in downstream tasks. We present COAS2W, a Chinese spoken-to-written corpus of 10,004 utterances from older adults, each paired with a written version, finegrained error labels, and four-sentence context. Fine-tuned lightweight open-source models on COAS2W outperform larger closed-source models. Context ablation shows the value of multi-sentence input, and normalization improves performance on downstream translation tasks. COAS2W supports the development of inclusive, context-aware language technologies for older speakers. Our annotation convention, data, and code are publicly available at https://github.com/Springrx/COAS2W . Category Example Context Constituent Omission e.g., subject omission 到了月底的时候，跑到我母亲这儿。 At the end of the month, went to my mother. 到了月底的时候，我家邻居跑到我母 亲这儿。 At the end of the month, our neighbor came to my mother. 我们在南市住，有个邻居啊，他生活也够困 难的。到了月底的时候，跑到我母亲这儿。 We lived in Nanshi, and there was a neighbor his life was pretty hard too. At the end of the month, came to my mother. Disordered Syntax e.g., improper clause order 南市住的话，她要是回一趟咸水沽的 话，每次回去一趟起码得将近半天差 不多。 If living in Nanshi, if she wanted to go back to Xianshuigu, each time going back would take almost half a day, more or less. 从南市到咸水沽，她每次往返需要半 天。 From Nanshi to Xianshuigu, each round trip took her half a day. 我们家在南市住，南市平房，现在食品街那 儿。南市住的话，她要是回一趟咸水沽的话， 每次回去一趟起码得将近半天差不多。 Our family lived in Nanshi. Nanshi had single-storey houses, now it's where the Food Street is. Living in Nanshi, if she wanted to go back to Xianshuigu, each time going back would take almost half a day, more or less. Constituent Errors e.g., incorrect use of personal pronouns 我弟妹说让我们把家腾干净了，我 们要来住。 My sister-in-law said we should clear out the house, we're coming to live here. 我弟妹说让我们把家腾干净了，他 们要来住。 My sister-in-law said we should clear out the house -they're coming to live here. 我弟跟我妈说他们下个月就来。我弟妹说让 我们把家腾干净了，我们要来住。 My younger brother told my mom they're coming next month. My sister-in-law said we should clear out the house, we're coming to live here. Constituent Redundancy e.g., self-repair(speaker restates or corrects) 我们哥五个哥六个觉得一定得这么办。 We five or six brothers felt that this was definitely the way to go. 我们哥六个觉得一定得这么办。 We six brothers felt that this was definitely the way to go. 我们哥五个哥六个觉得一定得这么办。我们 认为既然是老太太的房子，那么就应该作为 老太太的遗产，咱们哥六个应该共同继承。 The five of us, or six of us, all felt it had to be done this way. We thought since it was the old lady's house, then it should be treated as her inheritance, and the six of us brothers should inherit it together.