Detecting Non-literal Translations by Fine-tuning Cross-lingual Pre-trained Language Models

Human-generated non-literal translations reflect the richness of human languages and are sometimes indispensable to ensure adequacy and fluency. Non-literal translations are difficult to produce even for human translators, especially for foreign language learners, and machine translations are still on the way to simulate human ones on this aspect. In order to foster the study on appropriate and creative non-literal translations, automatically detecting them in parallel corpora is an important step, which can benefit downstream NLP tasks or help to construct materials to teach translation. This article demonstrates that generic sentence representations produced by a pre-trained cross-lingual language model could be fine-tuned to solve this task. We show that there exists a moderate positive correlation between the prediction probability of being human translation and the non-literal translations{'} proportion in a sentence. The fine-tuning experiments show an accuracy of 80.16{\%} when predicting the presence of non-literal translations in a sentence and an accuracy of 85.20{\%} when distinguishing literal and non-literal translations at phrase level. We further conduct a linguistic error analysis and propose directions for future work.