In this paper, we focus on the task of multilingual machine translation for
African languages and describe our contribution in the 2021 WMT Shared Task:
Large-Scale Multilingual Machine Translation. We introduce MMTAfrica, the first
many-to-many multilingual translation system for six African languages: Fon
(fon), Igbo (ibo), Kinyarwanda (kin), Swahili/Kiswahili (swa), Xhosa (xho), and
Yoruba (yor) and two non-African languages: English (eng) and French (fra). For
multilingual translation concerning African languages, we introduce a novel
backtranslation and reconstruction objective, BT\&REC, inspired by the random
online back translation and T5 modeling framework respectively, to effectively
leverage monolingual data. Additionally, we report improvements from MMTAfrica
over the FLORES 101 benchmarks (spBLEU gains ranging from $+0.58$ in Swahili to
French to $+19.46$ in French to Xhosa). We release our dataset and code source
at this https URL.

本文描述了我们在 2021 年 WMT 共享任务：大规模多语言机器翻译中针对非洲语言的多语言机器翻译任务，提出了第一个多对多非洲语言翻译系统 MMTAfrica，并介绍了一种新的反向翻译和重构目标 BT&REC，可有效利用单语数据。通过 MMTAfrica 在 FLORES 101 基准测试中的结果展示，取得了重大的改进和进步。