U niversal D ependency Treebank for X ibe (2020)

Abstract: We present our work of constructing the first treebank for the Xibe language following the Universal Dependencies (UD) annotation scheme. Xibe is a low-resourced and severely endangered Tungusic language spoken by the Xibe minority living in the Xinjiang Uygur Autonomous Region of China. We collected 810 sentences so far, including 544 sentences from a grammar book on written Xibe and 266 sentences from Cabcal News. We annotated those sentences manually from scratch. In this paper, we report the procedure of building this treebank and analyze several important annotation issues of our treebank. Finally, we propose our plans for future work.

## introduction the xibe language (iso 693-3:sjo) is a tungusic language spoken by members of the xibe minority group of china. based on the 2010 population census of china, the population of the xibe minority is no more than 200,000 1 . xibe people are mainly distributed in northeastern china, including heilongjiang, jilin and liaoning, and northwestern xinjiang uygur autonomous region. however, active native speakers mainly live in cabcal xibe autonomous county and adjacent regions in xinjiang. the number of native xibe speakers has dropped below 40,000 and continues to decrease. therefore, the xibe language is considered a severely endangered language by unesco 2 . there is a limited amount of linguistic studies pertinent to the xibe language. @xcite provides a survey on xibe language research since the 1970s. most of the previous studies are either theoretical description of this language or comparative studies with other languages, including chinese, manchu, and mongolian. however, there is no corpus or any computational tool available for this language so far. in cabcal xibe autonomous county, there is a single newspaper written in xibe, cabcal serkin 'cabcal news', which provides an invaluable resource for linguistic research. therefore, to start the process of building nlp applications for this low resourced language, we first aim to create a syntactically annotated treebank based on texts from this newspaper. we choose the universal dependencies (ud) framework @xcite to create a dependency treebank for the xibe language. the ud project has been developed for consistently constructing treebanks for many different languages cross-linguistically, aiming to capture similarities as well as idiosyncrasies among typologically different languages @xcite . the existing universal guidelines 3 have been widely used for a wide range of typologically different languages. thus, we expect that they will be usable for xibe without much adaptation. xibe is an agglutinative language with rich morphological inflections. we decided that annotating word features as detailed as possible will allow us to make available as much syntactic and semantic information as possible. the remainder of this paper is organized as follows: in section 2, we provide a comparison of xibe and manchu, and explain the differences between written and spoken xibe. we introduce details of the corpus, including transliteration and pre-processing, in section 3. in section 4, we discuss several important annotation issues in part-of-speech and syntax. we summarize our work in section 5. ## annotation issues xibe is one of the tungusic languages. like other tungusic languages, it has agglutinative morphology. xibe morphology mainly focuses on verbs in that verbs are marked for tense, aspect, mood, and voice, but also for converbs and participles. xibe phrases are head-final, both on the phrasal and the clausal level. the canonical word order is subject-object-verb (sov) (but see section 4.3), and arguments are marked for case. figure 1 4 shows a xibe sentence in canonical order, in which muse 'i' is the subject, mini juwe gala 'our two hands', in instrumental case (marked by i), is an adjunct to the main verb, ice usin tokso 'new muse me w gala q us n to so be l bume a amb 18-20 gu he o _ _ _ _ _ _ _ _ 18 gu gu x _ _ 22 nsubj _ @xmath0: fragment of the multi-word expression gu he o, gung he cgo, 'republic' in conll-u format. in the following sections, we will discuss several language phenomena in xibe, with a focus on the annotation decisions we have made for these phenomena. ## conclusion in this paper, we have shown the procedure of building the first xibe treebank using universal dependencies. this is an important step towards the documentation of xibe, for which little previous research exists due to its low number of language resources. along with the treebank construction, we document several language specific phenomena. for future work, we will continue collecting and annotating sentences from cabcal news and xibe elementary textbooks to expand our treebank. at the same time, we will also conduct corpus-based linguistic research on the language, and we will start investigating parsing approaches that will work for such a low resource language.