B i S ync: A Bilingual Editor for Synchronized Monolingual Texts (2023)

Abstract: In our globalized world, a growing number of situations arise where people are required to communicate in one or several foreign languages. In the case of written communication, users with a good command of a foreign language may find assistance from computer-aided translation (CAT) technologies. These technologies often allow users to access external resources, such as dictionaries, terminologies or bilingual concordancers, thereby interrupting and considerably hindering the writing process. In addition, CAT systems assume that the source sentence is fixed and also restrict the possible changes on the target side. In order to make the writing process smoother, we present BiSync, a bilingual writing assistant that allows users to freely compose text in two languages, while maintaining the two monolingual texts synchronized. We also include additional functionalities, such as the display of alternative prefix translations and paraphrases, which are intended to facilitate the authoring of texts. We detail the model architecture used for synchronization and evaluate the resulting tool, showing that high accuracy can be attained with limited computational resources. The interface and models are publicly available at https://github.com/jmcrego/BiSync and a demonstration video can be watched on YouTube https://youtu.be/_l-ugDHfNgU .

## introduction in today's globalized world, there is an evergrowing demand for multilingual communication. to give just a few examples, researchers from different countries often write articles in english, international companies with foreign subsidies need to produce documents in multiple languages, research institutions communicate in both english and the local language, etc. however, for many people, writing in a foreign language (l2) other than their native language (l1) is not an easy task. with the significant advances in machine translation (mt) in the recent years, in particular due to the tangible progress in neural machine translation (nmt, @xcite , mt systems are delivering usable translations in an increasing number of situations. however, it is not yet realistic to rely on nmt technologies to produce high quality documents, as current state-of-the-art systems have not reached the level where they could produce error-free translations. also, fully automatic translation does not enable users to precisely control the output translations (e.g. with respect to style, formality, or term use). therefore, users with a good command of l2, but not at a professional level, can find help from existing computer-assisted language learning tools or computer-assisted translation (cat) systems. these tools typically provide access to external resources such as dictionaries, terminologies, or bilingual concordancers @xcite to help with writing. however, consulting external resources causes an interruption in the writing process due to the initiation of another cognitive activity, even when writing in l1 @xcite . furthermore, l2 users tend to rely on l1 @xcite to prevent a breakdown in the writing process @xcite . to this end, several studies have focused on developing mt systems that ease the writing of texts in l2 @xcite @xcite @xcite . however, existing studies often assume that users can decide whether the provided l2 texts precisely convey what they want to express. yet, for users who are not at a professional level, the evaluation of l2 texts may not be so easy. to mitigate this issue, researchers have also explored round-trip translation (rtt), which translates the mt output in l2 back to l1 in order to evaluate the quality of l2 translation @xcite . such studies suggest that it is then helpful to augment l2 writing with the display of the corresponding synchronized version of the l1 text, in order to help users verify their composition. in such settings, users can obtain synchronized texts in two languages, while only making an effort to only compose in one. a bilingual writing assistant system should allow users to write freely in both languages and always provide synchronized monolingual texts in the two languages. however, existing systems do not support both functionalities simultaneously. the system proposed by @xcite enables free composition in two languages, but only displays the final texts in l2. commercial mt systems like google, foot_0 deepl foot_1 and systran foot_2 always display texts in both languages, but users can only modify the source side, while the target side is predicted by the system and is either locked or can only be modified with alternative translations proposed by the system. cat tools, on the contrary, assume the source sentence is fixed and only allow edits on the target side. in this paper, we present bisync, a bilingual writing assistant aiming to extend commercial mt systems by letting users freely alternate between two languages, changing the input text box at their will, with the goal of authoring two equally good and semantically equivalent versions of the text. in this work, we are interested in a writing scenario that broadens the existing commercial online translation systems. we assume that the user wants to edit or revise a text simultaneously in two languages. see figure 1 for a snapshot of our bisync assistant. once the text is initially edited in one language, the other language is automatically synchronized so that the two entry boxes always contain mutual translations. in an iterative process, and until the user is fully satisfied with the content, texts are revised in either language, triggering automatic synchronizations to ensure that both texts remain mutual translations. the next paragraphs detail the most important features of our online bisync text editor. ## evaluation we evaluate the performance of our synchronization model bisync compared to a baseline translation model with exactly the same characteristics but trained only on the trn task over bidirectional parallel data (base). we report performance with bleu score @xcite implemented in sacrebleu foot_8 @xcite over concatenated en-fr and fr-en test sets. for tasks requiring an initial target e, we synthesize e from (f , e ) pairs following the same procedures used for generating the training set (see details in section 2). ## conclusion and further work in this paper, we presented bisync, a bilingual writing assistant system that allows users to freely compose text in two languages while always displaying the two monolingual texts synchronized with the goal of authoring two equally good versions of the text. whenever users make revisions on either text box, bisync takes into account the initial translation and reduces the number of changes needed in the other text box as much as possible to restore parallelism. bisync also assists in the writing process by suggesting alternative reformulations for word sequences or alternative translations based on given prefixes. the synchronization process applies several performance optimization techniques to accelerate inference and reduce the memory usage with no accuracy loss, making bisync usable even on machines with limited computing power. in the future, we plan to equip bisync with a grammatical error prediction model and a better handling of prior revisions: the aim is to enable finer-grained distinction between parts that the system should modify and parts that have already been fixed or that should remain unchanged. last, we would like to perform user studies to assess the division of labor between users and bisync in an actual bilingual writing scenario.